Got game? Easy enough question. Come on, if you are a developer, there is a good chance that the first program you wrote was a game. It might have been a clone of Break Out or PacMan, but at some point you probably thought that it would be cool to write a 3D game—something like DOOM.
If XNA piques your interest and you are a developer to begin with, then a switch over to the C#/XNA environment should prove a breeze. If you are not a developer then hope is not lost, since C# is not that difficult to catch onto. Of course, to make a decent game a lot of coding knowledge will be required. Luckily enough, there are many samples available for you to reference.