Now after a long wait the mostly used player for all operating systems is now available for iPad and download at itune store. VLC media player is an open source media player from VideoLan project. It is one of the most platform-independent media players available, with versions for Microsoft Windows, Mac OS X, GNU, Linux, BeOS, and BSD
VLC can play the video content of some damaged, incomplete or unfinished videos (like downloads) before the files have been fully downloaded. You can streem videos on your iPad directly from wifi using VLC media player
have a look at the screen shot from iPad running VLC.
You can browse the iTune and download the VLC from there or from appication site.