ghettoisation of riders:
for the mtb'ers trail centres, the perfect answer to all weather all year riding or the macdonalds of off roading?
for our road/commuters:
dedicated bike lanes protecting you from cagers or traeting cyclist as 2nd class road users?
I'm not a MTB'er (though I hope to pick it up this summer -- just gotta get a bike [that should thrill the Mrs.]), so I can't speak to the bit about trail centres. But I have all sorts of thoughts about about bike lanes, yes I indeedely-do. Most of them bad...
I commute year round (mostly) by bike and there are millions of miles of bike paths, you just call them something different in your tongue: city streets. I'm pretty happy to take the street a block or two off of the main street -- less traffic, less hatred and you usually stumble upon something you'd never seen before. These benefits aside, trails are nice if you are converting old rail beds to make areas more accessible (like the Munger Trail here in Minnesota), but shunting me off to the side is something up with which I will not put!
Cagers need to see bikers on the road. Bikers need to see bikers on the road. Potential bikers really need to see bikers on the road. The idea the cars are the only things allowed on the streets is something that has to be put to a quick death and as politely and painlessly as possible. Drivers will have to become aware that they are not the sole users of this infrastructure, planners will need to become more aware of this also. But allow me stress what I believe most strongly; bicyclists need to understand this more than anyone.
Allowing ourselves to be shuffled to paths that lead nowhere, travel in unnecessarily meandering directions and separated from the traffic at large seem to me to enforce the idea that a bicycle is not a mode of transportation, not a useful member of the infrastructure, but a toy, a weekend conveyance to be used only on the nicest of days and to get a fresh air and some exercise when you have a little time to kill. This thinking is wrong and if this idea is to be put down, integrating traffic must be done.
Obviously, drivers need to be aware of bikers, but bikers need to become more aware of cars and to get your "combat riding" skills sharpened -- taking the lane, following the traffic direction (lights, signs, etc.) when with other vehicles, crossing the street when it's your turn and so on. If you are shuffled off to some crumbling strip of ancient asphalt and expected to be out of sight, you will also be out of mind and that is the opposite of safety.
I'm not against safe areas at intersections, areas the alert drivers to the presence of bikers and give bikers some shelter from the dreaded "right hook," but I do not believe that a stand-alone strip of tar away from driver and intersections helps anyone. A driver at an intersection is busy enough trying to just keep all vehicles in all directions at that specific crossing in view and another intersection, typically poorly marked is just 5 meters away where bikers are supposed to be. After making a turn, drivers are just not going to continue to keep looking in the direction they with to turn in order to see yet another intersection.
I believe that the comingling of various types of traffic is good -- it keeps people (generally) paying more attention, moving more slowly and carefully and it helps make everyone more honest about following traffic direction from lights, signs and road paint. There is no room nor money to create another completely separate infrastructure for bikes, another for walkers and possibly a third for trains/trolleys in most cities. Mutual respect and acknowledgement is the only way that we can safely travel together on streets in an urban environment.
This is not to say that I don't believe that there shouldn't be trails, no, far from that. I would love to see an eventual linking of old rail beds into a bike trail system that crosses the country, a way that bikers can travel from coast to coast, Canada to Mexico. But this is different from regular road traffic as is pretty obvious.