With built-in YouTube, SlingMedia Player in the works, and now Ustream announcing an iPhone viewer, is Flash still going to dominate most-wanted lists, or is Apple actually halting Adobe’s video advance? We don’t know, but we do know we’re really excited by the mobile video options we’re already seeing:

Ustream has developed an application for the 3G iphone that allows you to watch Ustream anywhere w/everyone. Regardless of where you are at and what you are doing, you can choose to be in the moment with others in a shared live experience around a live event. If you are out-on-the-town and know that a guest speaker at a major conference is “going live” and want to watch live and be-in-the-crowd, then you can with this application. You will be able to watch the Inauguration LIVE on Ustream with chat.

If Apple approves the Ustream Viewer in time, who’ll be watching?