Bonus time at the employer means it's time for me to start looking for N+1. My road bike (08 Fuji Newest 1.0) is more than enough bike for me right now. What I'm looking for is fall and winter riding fun, so I am trying to decide between Mountain and Cyclocross. I of course have dreams of some competitive riding in either discipline, though I have no idea where one gets started in this. As these bikes are generally built less for lightness than for strength, I don't have nearly the concerns I did about buying a road bike. I know there are forums that specialize in this, but wondering what the clydes ride on MTB and Cyclocross.
Also, no idea if Im looking for downhill or standard trails on the MTB scene either.
I guess a lot depends on what type of riding you have access too. If you don't have access to trails locally then a mountain bike might not make sense. Maybe a little research will might help you decide. Also, a Cyclocross bike is close enough to a road bike, that it may not make sense in some ways. I have a road, Cylocross and mountain bike. I don't plan to race the cross bike, but use it as my training/errand runner or anytime that I know that I am going to ride gravel or really rough road. Also, it makes my road bike feel like a rocket ship when I switch to riding it for a organized ride, or now a triathlon. The mountain bike is something new this year, but I am so glad that I started mountain riding. It is a different skill set that has paid big dividends on my road bike. So for me, the mountain bike makes more sense since there is more difference between it and your road bike. Also, a mountain be can be a good in town commuters as an option, even though cross bike can be too. As to down hill verses trail, I would start with a standard trails first before moving on to downhill riding.