That is not how filesharing is implemented on the iPad. I built an iPad app based on the initial (beta SDK) description & I basically gave up on using the file sharing feature once I saw how incredibly incompetent the current implementation is. Apple really dropped the ball here.

Awesome! Having the iPad show up as a share is great and definitely a step in the right direction. Having all files available to all your devices as the default (and with browser synch) is the holy grail imho.