Compression damping, multi stage, adjustable. Serviceable and customizable by the end user.
Most suspension for MTBs is rudementary at best. There's the odd piece of equipment that comes stock performing adequetely, but overall today's suspension needs work.
Marzocchi is the worst in terms of compression and rebound damping. Manitou's got promise, but its never really really been 'there'. Rock Shox's Motion Control is great in stock MTB terms, but its still not as good as it could be. Fox has the best 'feeling' compression damping, but its not servicable by the user. I'd pick Rock Shox over any other stock product because it performs well, easy to maintain and service, and its light and structurally sound.
That said, there's a Mojo kit going into my Boxxer, and I'm also getting the new Mojo 999 cartridge kit to test that replaces all the internals within the 888.
For rear shocks, Manitou 6 Ways are way over-damped for most bikes, unless you're riding them with a high leverage frame. Same goes for 5th Element shcoks, which are leaving the MTB market apparently. The newer Fox shocks are the best, in my opinion for compression damping for most bike designs, and offer the easiest and most effective after market custom tunability. I have yet to try extensively an Avanlanche shock, but I hear nothing but praise for them.
One thing to remember is that with good suspension, it really shouldn't matter what frame design you're using.