I was getting the black screen, but the library tab seems to be working now. I like the idea very much, and hope to see more features implemented (such as what you see when you view your library in steam [achievements, news, links, etc]). Also, nice job with the trading cards link, that will come in handy (though it isn't showing on the most recently added games).
Sucks to hear about firefox, would love to see all the chrome features make their way over. On the plus side though I saw you added an opera version, which is all kinds of awesome
Yeah Opera was kind of tricky, but I got it working. Right now I'm working on an Opera Next version, which should be similar to the Chrome version (Opera Next uses webkit and basically the same type of plugins).
I have quite a bit planned for the library tab like achievements, news, links, and the like but will also list DLC, cards and things like that. I'm planning on adding a "View this in your library" button the the app page if you own a game.
Speaking of cards, the newest ones aren't showing up yet with a link because Valve has not marked them in their database yet as having cards. For example, they're not listed here or on the right hand side of the app page under "Features". I imagine this will get fixed in the next few days.
I also fixed a bug with the profile backgrounds - the database was initially set up as having a tinyint field because originally there were only 15 or so backgrounds to choose from. Now there are almost 200 backgrounds, so I've bumped that field up to an integer so now Valve can release 2,147,483,647 backgrounds before I have to change it to a bigint. :P