I work in C#, and I\'ve been pretty lax about using using blocks to declare objects that implement IDisposable, which you\'re apparently always suppose
Unfortunately, neither FxCop or StyleCop seem to warn on this. As other commenters have mentioned, it is usually quite important to make sure to call dispose. If I'm not sure, I always check the Object Browser (Ctrl+Alt+J) to look at the inheritance tree.