These threads are basically excuses to build dream bikes rather than being of great practical use. Not that there's anything wrong with fancy bikes, I've come to their defense many times in this forum. But unless your commute requires you to cross the Arctic Circle, the bike you ride all summer should do just fine. In the name of safety and reliability you may need some additional accessories, or some different tires. That's just good sense. But a titanium frame? I hate to imagine people reading this and actually believing that a steel bike is going to melt under winter conditions. If you take even the most basic care of your bike, it will be fine, and neglected titanium bike would be just as bad as a neglected steel bike.

By all means, if you want a fancy winter bike, have fun with it. But a titanium cyclocross bike with disc brakes is going to be a pretty damn "ultimate" commuter all summer, too. That's sort of the point I'm trying to make.