yeah, mostly baseline prestige. CSU is a middle ground conf - they have C baseline - which is actually a big improvement. the D prestige schools (all the little confs), those can win titles and hit a whopping A-.
except memphis - they are B baseline. i think. but a big part of prestige is also conference prestige - which is just the average prestige of the conference. the BCS schools with B baseline still have an advantage over memphis, prestige wise, because their confs are generally higher prestige (not necessarily, but probably almost always).