Whoops! Looks like Mr Ahston Kutcher may have fallen prey to Firesheep, the Firefox extension which sniffs out and hijacks browsing sessions.
Hopefully the guy or gal who has control of his account is just a Firesheep vigilante with no cruel intentions, but I suppose we'll probably find out soon.
Either way, in the future Kutcher should be sure to use some kind of Firesheep protection method such as BlackSheep, Fireshepherd</a, or HTTPS Everywhere. Either that or he's gotta stop using shady Wi-Fi hotspots! [Twitter]