Source: http://feeds.gawker.com/~r/gizmodo/full/~3/DrRDw9Usiv4/project-natals-lag-timed-at-110-of-a-second
Ever since our hands-on, we've been shamelessly excited about Project Natal...except for one key piece: The slight but undeniable lag. And now, MTV has actually put the difference between your movement and onscreen response to a stopwatch.
Over the course of several demos, MTV found that the lag ranged from .08 seconds to .12 seconds, and .10 proved to be a pretty consistent average. (You can time .10 seconds here.)
During our demo, I likened the delay in a driving game to steering an old Cadillac. Indeed, as an input device alone, such a delay will mean certain gameplay situations just aren't possible (Natal might not make the best jet simulator).
However, I still see the delay as a non-issue for the aspect of Natal that's still gone without mention by most publications—that of head tracking. You'll see what I mean in this demo by Johnny Chung Lee who, it just so happens, works on the Natal team now. The same can be said for vocal commands, facial recognition, and heck, even just spotting your exact position in a room. [MTV via Kotaku]