I love webOS. I think the software is absolutely fantastic, the hardware is meh, and the apps are down right embarrassing. Even with a giant pile of cash behind it, webOS will never be the leading mobile platform of choice for consumers unless some things change.

Advertising

In the U.S., advertising is what makes users buy products and typically there is only one source for advertising in mobile. That source is the carriers, and carriers only advertise when they have an exclusive (or at minimum a customized device). The only exception to this is the iPhone in which Apple handles all of the advertising directly. But Apple is an advertising giant that has no equal in the tech world.
HP has proven that they don’t know how to advertise webOS and if their current trends continue with devices, they want to stay away from carrier exclusives as much as possible. Which means carriers won’t take over the advertising for them which means people won’t buy devices.
The only way to fix this is to either make the devices carrier exclusive, allow carriers to heavily customize devices, or figure out how to advertise webOS on your own. I would recommend doing all of the advertising in house but HP needs to figure out a better way to advertise than what they have done in the past.

Hardware

The Pre, Pre Plus, Pre 2, Pre 3, and Veer have all been pretty much identical phones with slightly different specs and in different sizes. The problem with this is the portrait slider is the least common from factor that people buy. The flip phone, candy bar, and slate are by far more common form factors and coming in close 4th is the landscape slider. Way under that is the portrait slider, and by limiting themselves to this form factor they limit themselves to a very small segment of the market. I know they will probably eventually make a slate device but that is where the second half of the hardware problem comes into play.
Not only has HP locked themselves into a certain form factor but they have never had innovative hardware specs or options available on their phones. They have always been trailing the market in hardware specs which makes the phone stable but not groundbreaking for features. Inductive charging and the yet-to-be released tap to share are two areas where HP has tried to be innovative. It is unfortunate that they have been behind on gyroscopes, qHD/retina displays, NFC, front facing cameras, 4G, HDMI video, etc. This lack of innovation keeps people from being excited about their products and keeps HP from being a leader in the mobile space.
To fix there hardware problems they need to take more chances in hardware specs and features, and if they are going to stick with the portrait slider they need to perfect it. After having played with every portrait slider they have made, they still have a long way to go before they reach the usability/functionality where they want to be. BlackBerry hardware has always been better and even the Dells Venue Pro does a better job at making a portrait keyboard usable.

User Experience

When webOS was first announced their user interface blew everything else out of the water. It’s still a slick way to manage apps and to move around the device but other manufacturers have discovered this already and are adjusting accordingly. As you can see in the screenshots, Windows Phone 7, BlackBerry QNX, and even Apple iOS are all going to have some sort of card layout to switch apps in the near future. Even Android has software that will let you emulate this functionality to a degree.
So if app switching is going to be essentially the same between every mobile OS the only other innovation is how to use the screen when not in applications. There are essentially only two methods to handle the screen when not in an application. Either clutter the screen with quick information via tiles or widgets, or keep the screen relatively static with app launchers a la iOS, webOS, and BlackBerry OS. WebOS is sticking with the static launcher approach but they have one big thing to get over if they are going to stay in that space, apps.
To fix this they need to be more innovative in their software with cloud computing, allowing 3rd party plugins, and an ecosystem that Android and BlackBerry can’t touch. Apple has an ecosystem that doesn’t let users escape and HP needs something similar if they want to make a consistent user experience. But in order to do that they are going to need to branch out into music and video services or seamlessly allow 3rd parties to tie into those services on the device.

Apps

WebOS has always been behind on apps. It is embarrassing that Windows Phone 7 launched almost two years after webOS and they already have more apps than webOS and they even have more big name apps than webOS which is what the general public cares about. Sure webOS got some apps before Android but now they are forgotten about and are typically the last to get an app behind iOS, Android, BlackBerry, and WP7 if they even get an app at all.
Being behind in apps is not only a problem for users but HP isn’t able to create a consistent app development experience for developers. First was the SDK but that didn’t have enough access to the hardware and was limited in customizability. Next was the PDK which was great for porting objective C apps from iOS and it solved some problems of hardware access. The PDK never seemed to be fully functional and developers who wanted to learn objective C might as well just develop for iOS and leave it at that. The return on investment for webOS porting was not worth developers time because there was nothing a webOS phone could do that an iPhone couldn’t (see hardware) and there weren’t enough users to make it profitable. Now HP is pushing Enyo. Enyo is a mashup of the SDK and PDK which has more hardware access but is easier to develop than objective C. This is great but it is another language that now would require developers to learn a language just for one mobile platform.
The way HP can fix this is to stick with a single development platform and to pay a lot of money to get big businesses to invest in webOS apps. They need to go after the big names like Netflix, Hulu, Amazon, Google, twitter, facebook, etc. They also need to get more 3rd parties building plugins for their music player, pictures, contacts, just type, etc.

Wrap Up

I know webOS has some features that no other mobile OS has and there are rumored developments like continuous computing that would be amazing for mobile devices. But until HP actually delivers on these rumors they are still just cloud dreams and by the time they are out someone else will have already implemented or announced a similar feature.
What do you guys think? Will webOS ever catch up in the mobile space? Putting webOS on HP laptops is a completely different story but unless some things change I don’t see webOS ever being a major player in the mobile space.