I just noticed your mention of "Winter", which hasn't been addressed in other posts I've read. Things do get dicey here in the wintertime, and for that reason access to public transportation is highly useful if you're living car free. Temperatures can drop into the single digits in December and January... sometimes even lower overnight. More typical temperatures those months are in the teens to low 30s. So you have to be prepared for the cold. Additionally, we get snow. Some years we get a lot, other years the city only sees a handful of big dumps. When the snow does come down, the roads get plowed within a few hours. Residential neighborhoods are the last to get plowed, while major arteries are the first. The plows will leave walls of snow along the roadside. Sidewalks and intersection ramps can become icy and clogged with snow. Frankly on a snow day, and even the day or two after sometimes, you're probably better off either staying home, or taking public transportation, or a fat snow bike. But it's not all bad -- the snow is not constant, and the cleanup starts almost as soon as the first accumulation occurs. But it's definitely not road biking conditions in December and January. And the ski canyons really do become inaccessible those times of year to cyclists due to traffic, high snow walls, and temperatures.

If you're living in flat areas near public transportation you'll be fine throughout the winter. If you are living in the foothills, and without proximate public transportation, and need to use your bike to get to the public transportation, December and January won't be much fun. But there are foothill neighborhoods that are well serviced by public transportation. Use the map I linked to in a previous post to identify where they are. Mine happens to be, because the bus that takes people from the main arteries to the ski resorts passes a tenth of a mile from my home.