I have previously reviewed google maps controls for winforms.
But now I Just reviewed the options for googlemaps in asp.net. There are MANY so I will not go into all of them and just point to what I found to most FREQUENTLY updated and yet feature loaded. (The frequency of update is very important for commercial use of a control. Since two days without your users being able to see their favorite map could be disastrous!)
Here it is : http://googlemap.codeplex.com/