I've been using my iPad for half a week now and I just love it.
Although there is already a huge number of iPad apps, most of them -surprisingly- very well designed, I couldn't help but notice some of the big names missing.
Lots of those missing apps have awesome iPhone equivalents and yes I can just install them to my iPad right away, but deep inside I know that their iPad versions would be way more powerful, like Instapaper (iTunes link).
Although it's a bit early, much like when App store was firstly introduced to iPhone, here is my list of apps that I am waiting to be created/released in the not-so-distant future:
Well, I don't use Facebook that often and mobile Safari for iPad renders Facebook interface just like in the desktop version, but I guess a native iPad app could make the difference. Too bad Joe Hewitt) decided to stop creating iPhone apps.
Delicious
This app has a true potential on the iPad. Having a central point to organize/view your bookmarks (ala Instapaper) can make Delicious for iPad a killer app. So, who's gonna build it first? :P
Google Reader
There is already Reeder for iPad in the works (you can view some early screenshots here) so it's really a matter of time to have a truly awesome gReader app for iPad.
Flickr
Many might point out that a Flickr app in a device with no camera would be just useless. But Flickr is a lot more than just uploading photos. Organizing your stuff & socializing through Flickr is probably more important and this is where an iPad app can truly shine.
Spotify
I really wanna see a Spotify iPad app. This would make me use my Macbook/iMac only for work and just have the iPad for nearly everything else (well except World of Warcraft and Steam games I suppose).
Classics
Classics (& Stanza) must get an iPad makeover. So freaking simple.