depends....usually around 20 for drums (around 14 for the actual mics plus samples/triggers), 2-8 rhythm guitars (double/quad tracked, multi mics etc), 3 bass, leads depend on the style, shitloads of vocals....went up to 30 for some projects that included lots and LOTS of layers, choirs, and different styles.
generally speaking, if i want a specific effect for something (lets say a radio-style vocal with lots of fx) i'll put it on a new track rather than automating fx levels and plugins on/off.
so, around 60 for the tracks, plus groups...i group EVERYTHING. toms, kicks, snares, OH, guitar 1/2, bass, vocals sorted by style, leads, melodies, synths....everything.
unlimited track count is one of the huge advantages of digital vs analogue. why not make good use of it?