Did you check your timers? Is your game run loop operating at a fixed FPS? Debug vs release builds can often involve different precision that may effect this, especially if you're using the clock() function (which you shouldn't be if you are). Also, check your optimization properties. Try using just the project defaults (typically, optimize for speed is enabled with all other options disabled). Continue playing with the options until you can see a difference. I've never had problems with the 2010 compiler, but I remember running into constant issues with the VC 6 compiler optimizing code in ways it shouldn't have (sometimes outright deleting code!).
Other than that, profiling your code will be the only way to track down the issue. You may need to manually disable code and enable them one at a time to trace the issue.