His French is excellent. A little bit of accent, as can be expected, but his grammar is great.
This said, this is not a spontaneous speech, so he probably rehearsed it. But still impressive.
It is amusing to see that the GOP two top contenders have spent a substantial amount of time in France, Romney as a missionary and Gingritch as a kid. What happened to the GOP who disliked French looking Kerry?
The subtitles are hilarious, though I had a hard time reading them and listening to him at the same time. No connection whatsoever.
(I cringed when I saw the ad. When will the US get rid of this ridiculous anti-French feeling).
ADDED afterwards.
http://videocafe.crooksandliars.com/heather/french-mitt-romney
I read this piece by crooksandliars and had to go back and listen to the video. One striking thing is that Romney pronounces the letter "ü" well, even though it is hard for an American to pronounce (it took 10 years for my husband to master it)/. Generally speaking, even though with a little bit of an accent, his pronounciation is correct. He may not speak French everyday, but by all reasonable standard, his French is good.