Choosing an appropriate type of reverb for the situation (convolution, digital, analog, natural room reflections) is important.
However, a dimension to reverb that I think many people overlook is how it is mixed! A reverb return should be treated with as much care as any actual instrument track in a mix!
- As I think has been mentioned, if lots of reverb is used, then preferably lots of DIFFERENT reverbs should be used. A lot of the same reverb will clash with itself and cancel itself out, just like two instruments panned the same way with similar harmonic content. This will cause you to use MORE reverb, which makes everything a muddy mess.
- The panorama of reverbs is important too! If you are using a DAW that allows the discreet manipulation of the two channels of a stereo return, you can easily set the width of any return track. However, you can also do this if you use a reverb with a "diffusion" setting. This setting will determine how wide the reverb will be. Reverbs at the same panning can clash just as easily as two instruments. Don't be afraid to pan some reverbs right or left-heavy even. Sometimes it can be a really cool effect even, if you have, say, a guitar with a reverb, to pan the reverb to the OPPOSITE side of the guitar.
- Possibly most overlooked is the option of EQ'ing a reverb return! To make a reverb more noticable, boost a high shelf. To make it less noticable, lower it (this is a very good idea if you're trying to use variable levels of reverb to establish depth, but don't want the 'verb to be noticable). Adding lows to a 'verb will increase the perception of the size of the reverb, while cutting lows will make it sound thinner.
- Pre-delay doesn't JUST have to be a "neat effect". You can use just a little bit (like 20 ms) with a 'verb for snare/toms to help the initial hit stand out on its own better without becoming muddy.
Finally, remember that reverb isn't just "some crazy effect" all the time. Reverb can be used to put various elements of a mix (or even the entire mix) in a specific acoustic space. More usefully, it can be used as an additional means of separation, to add depth to a mix. When you want something to sound like it's further away from the listener, use more reverb! You can use it for instance to audibly put backup singers behind a lead. Or you can automate a reverb send if you want something to sound like it's getting closer or further away by degrees.
Also, digital isn't always bad. I usually reach for a digital 'verb for drums on a good amount of metal that I mix, and those bands wouldn't want it any other way, bright, grainy texture and all!