I've been going through the same thing here. As the weather turns cold and wet, I'm less prone to want to bike in. Frankly, I still don't think it's likely that I'd ever decide to ride to work in the rain, especially a cold autumn rain. Not only is the cold/damp miserable, but I just don't like exposing the bike all its fiddley bits to the wet.
But I'm working on doing so at least on days when the chance of rain is slight, then it's just cooler weather to deal with. Well, that plus the fact that it's increasingly still dark when I ride in. I've been buying into more riding gear that I didn't need before - base layer, arm & knee warmers, etc. As the season progresses, I'll probably buy what's appropriate as I need it.
Tied to that - and just as important for living with a bike year round - I think I'll eventually need to spring for a better headlight. I had a 1-watt Planet Bike LED headlight on my road bike, and second on my MTB. I put the one from the MTB on the Surly as soon as I brought it home. Shortly thereafter, I took the second one from the Raleigh and also put it on the Surly. That comes up to adequate lighting for the dark stretches of road and canal path, but only adequate. For reference, I've long spent money on playing at road rallying in the winter time, and have got very accustomed to having excellent headlights and auxillary lights on my cars. So, I suppose I'm a bit spoiled. But you can't have enough well aimed light out ahead of you. Now I'm looking into some of the higher end headlight systems, either rechargeable or powered by a dynamo hub. But I don't quite have the clams to drop on that set up yet.
Anyway, I almost feel that I can't wait till winter hits and its cold enough that it will no longer rain or thunderstorm. Sure, that means snow and more frigid air. But again, you can dress for that, and if I'm riding regularly, be in shape to deal with the cold, dry air will be a lesser issue. I've already built myself a winter commuter bike (back in February) with snow tires, so I can't claim that as an excuse...