Astute tipsters discovered some unprotected directories on Ubisoft's site, and we now have 20-second clips of Splinter Cell: Conviction and Assassin's Creed 2.
AC2 is up thar; SCC is down thar. These don't feature gameplay, QT events only. We're assuming these are meant to be played sometime at E3. Thanks to chillchillin and Byvar for the discoveries.