Gelatin
Boob inspector
In my opinion, the worst pieces of advice going round this forum are cutting out spill on tom tracks and brutally hi-passing overheads insanely high. I'm boosting loads of bottom in my OHs and automating my tom tracks - that's my tip for a good snare sound.
I agree with the OH's but I think that the tom tracks are a matter of taste really, depending on if you're going for a dry sterile type sound or a open roomy type of drum recording.
On topic - I usually record top/bottom snare but sometimes I end up throwing the bottom one and going the sample way instead, but that's mainly because I never get good results with the crap mics I have... lol.