There is a 'fad' for having a CX bike for the commute. It's generally down to the disc brakes folk are going for these.
Either a road bike or a CX will do, personally I have a road bike (3), and an MTB for off road. If you've got a mix or surfaces then a CX bike is quite good. If it's 100% tarmac, then get a road bike.
@fossyant , I'm only considering the CX, due to it's hybrid (correct me if I'm wrong) of MTB and Road/Racer. Which I believe would give me the strength of the MTB and the speed / agility of the Road/Racing bike.
Basically, I'm 149kg (give or take), and although I'm not looking at getting one this side of the year (at the minute), I'd like to be able to pick up speed on the roads for my commute and anything else I do, but it is predominantly all road cycling I do. The only "offroad" cycling I've done since being back in the saddle, was riding the Camel Trail last year, that's pretty much loose gravel, and then Coast to Coast (Ilfracombe to Plymouth) where some of it was dirt / mud, but so little of it we were soon back on the roads.
The thing I'm dubious about road bikes, is purely their build. Plymouth (along with everywhere else) is plagued with potholes and neglected roads. I'd hate to get caught in one and have a bike wr