Re: Joining the Club
If you want to jump into game programming with the 3 months of summer you have, I would start with C# (using Visual Studio 2008), then get into XNA.
I bashed out a simple game in XNA inside a day, I love it. With XNA you get results very quickly and it keeps you motivated to keep going. You really need the C# skillz first though. If you dive in to an XNA sample without understanding C# you'll get lost.
Don't listen to these guys telling you to start with C++. You'll spend hours and hours trying to get your code to compile - you'll pull your hair out, age several years, gain weight and develop strange sexual preferences, all because you left off an "&" in front of a variable name. I am sure i'll get flamed now by people saying "real programmers use C++".... bring it :P
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