I'm surprised nobody has mentioned, I would bet very heavily that the grill will be rounded, similar to the E92.
Look at this picture of a E90 M3 in testing: http://www.e90post.com/forums/showpo...58&postcount=7
You'll notice the hood on both the 2009 E90 and the E90 M3 looks similar. I don't think BMW is going to just curve up the edges of the grill and leave the chrome mustache, it definitely looks like they are going to make the grill similar to the E92. That hood just has some masking which hides the real profile and makes it seem more similar to the current E90.
That will definitely improve the looks of the E90 IMHO.