I have been riding road bikes for a few years. I ride to work everyday, but I just bought my 1st Mountain Bike, Novara Intrepid, two weeks ago. As a road rider I would never think of using a Camel Pack because of the heat. However, with all the bouncing around that I have been doing on the MTB it seems like it would be difficult to keep the water bottles in their cages. Do most of you use bottles or packs? Either way could you recommend a good hydration system for mountain biking?

Thank you in advance for your help.

I used bottles for a couple months before switching to a camelbak. Probably the best MTB related accessory I have bought.
I got a Camelbak M.U.L.E(bought it for $45 new!). It is a bit large, but it can hold a ton of water and has space for everything you will ever want to carry.I have even taken my DSLR camera with me on a couple rides.

Its mixed. Some people I ride with use bottles, some packs, some both. They'll put a sports drink in their bottle and just water in their pack. Bottles mostly stay put mostly. I use an Osprey Raptor pack and it is awesome.

Thank you for the information. I will take a look at both those packs.