I've been tempted by the same ad. I ride my mountain bike during winter/bad weather days and my road bike during nice weather. If I picked this bike up I could use it as my bad weather commuter (rain) and leave my mountain bike set up for winter.
A friend of mine at work commutes on a Diamondback mountain bike and hasn't had any major problems.
I would think it would have to suck pretty bad to not be worth $199. All I'd have to add would be some lights and a computer and I'd be in business.
So tempted...