I'm coming from my Droid X2. I've been looking into selling my unused laptop and buying a tablet all summer. I was originally looking at the TP, GalaxyTab/Xoom, and the iPad. I took the iPad off of the list fast because I've hated every Apple product I've ever used and I hate what Apple stand for (closed system, one size fits all). I then took the TP off because I didn't think it would be able to replace what I could do on my laptop- mostly because of it's small marketshare and app catalog. When it went on sale for $100, it was too good of a deal to pass up. I didn't even have to sell my laptop. I'm pretty happy for it considering that I got it for $100. If I paid full price, I probably would return it.
WebOS is very intuitive. I figured out the OS practically right away- much faster than learning Android (Even though that was the first time learning a mobile OS). Most everything works as you think it would
Damn near perfect size, weight, and thickness compared to the rest of the tablets.
There's no proprietary charger. I have a million USB cables and USB chargers, so if I lose the TP charger, I don't have to buy another one from HP. I can just get one out of the drawer.
Speakers are better than I was expecting.
Cards and the way you interact with them are pretty cool
While you cannot tweak it to the same degree as Android, tweaking is fairly easy to do.
Free box.net subscription and the ability to edit with QuickOffice will be useful
No extra USB ports. I would say no video out, but that's something I would never use.
The volume buttons are accidentally hit constantly
The browser is absolute trash.
-It does not like HTML5/CSS3 at all. It doesn't display pages right that IE would display.
-As previously said, the bookmark system isn't very good
-There is no way that I know of that gives you the option not to open a link in a new window. It's annoying when using a site like Digg and having to open and close new windows every 3 seconds.
-Scrolling past the screen vertically is kind of cool. Scrolling horizontally into the grey abyss is annoying.
-There is no indication of how far down you are on the page (AKA scrolling bar)
I like the scrolling pace of Android better. WebOS is much slower and won't scroll nearly as long.
Lack of a back button standard. In Android there is a physical/virtual back button. In iOS, the navigation is the same in almost all apps. In WebOS, the back button can be on the top left, bottom left, or in the app's menu. This makes navigation very annoying as every app is different from the last.
I miss the customization/widgets of Android's home screen. As much as I like the cards, I still want a regular homescreen. I love my phone's homescreen. It's just how I want it. When I look at the WebOS homescreen all I think is meh.
Like Android, it needs to be reset every couple of days to perform well.
The native apps are pretty buggy. I often have to wait several seconds for the screen to respond at all.
No Ctr-F in PDFs
Finding a page in PDF's is very annoying. I was looking through my school's course catalog which had over 600 pages. It took nearly a minute to get to the page on something that should take 5 seconds.
I want a section in the app drawer that has every single app on my device. You can have other tabs for games and what have you, but these should be duplicates. Having every app that I download go into a download section that has to be moved over is irritating.
Basic apps are missing- File Manager, Camera
The way it handles apps made for the Pre is pretty bad. Instead of display it on a fifth of my screen, make it bigger so I can actually use the app.
And the biggest thing on this list: There are no apps!
Keep in mind that this list is based off of stock WebOS. I just tweaked it according to one of the stickies, but I haven't really had much time to play with it to see the difference. Regardless, the negatives still have merit as a user should not be forced to tweak a stock product to make it work well.
I do like this device. There's a ton of dislikes on here, but that isn't to say that I dislike the TP. I do like it, but there's a ton of things that would make it better.