Yes...and no. Carbon has become very common and relatively inexpensive in recent years, as companies like Giant, Specialized and Trek offer complete bikes from under $1,000 to more than $10,000. Aluminum is still used as well, but primarily in either low-end bikes or stiff, featherweight climbers. And steel and titanium, both of which have their faithful disciples, are both most commonly found in framesets only (as in, build your own bike). As far as a price/weight/comfort ratio, carbon fiber seems to offer the most value. And sometimes lower-cost bikes feature the same carbon framesets as their (way) higher-priced brethren.