Great advice, I'll definitely check out World Mate Live. Sounds like a great app!
Here are some of my faves: Superpages Mobile - Local access to business listings, People, Movies, Theaters, Weather, Maps, WiFi Finder and Favorites. Cool app with small footprint.
Vlingo - the best voice recognition software I've ever used, way better than the native one on the BB. You can do way more, worth a look see.
Slacker Mobile and FlyCast - Streaming Radio...Slacker is just like Pandora and works very well on the 8900. FlyCast is cool if you're into Shoutcast, which I am.
Viigo - Phenomenal News & RSS reader, you can pick tons of channels within many different categories, I use it for all my sports, and weather.
FML - F My Life - One of the funniest blogs on the web, installs as an app but it just quickly links you to the site. Fun for killing time if you're waiting for a plane or train or bus.
Google Mobile App
That should keep you busy for a while