I get a brief pause, not nearly that often.  only several times a game.  Everything pauses for a sec, then continues on.  4 gigs ram, 8800 gts 640, amd64x2, vista 32b.  Hasn't interrupted my ability to play the game, it literally only lasts a second, didn't even think of it till I saw this post, but might as well add my 2 cents for information's sake.

I just did another game, this time looking out for it, and it didn't happen at all this time.  *shrug*.  no difference in what's running on my machine or anything.  I run x-fire so maybe it had been doing somethin' that earlier game.