It isn't enough but Microsoft will be able to say that they have a system that is now cheaper than the Wii. $199 for the Tard Plus is a good price point, although probably a year too late. $299 for Premium is an acceptable price point. It is still $100 cheaper than the PS3 offering and cash strapped parents may pick it up due to that reason alone. After all, GTA, Madden, etc. are all on the same systems and little Billy can go fuck himself if he bitches about it.
Microsoft should sell at least 4 million of these at this price point by the end of the year. If not, they are fucked.