One good reason why Putin himself is quiet is that he doesn’t know how to respond. His democracy may be a sham, but he still needs to take the sentiment of the Russians seriously. If he cannot control that sentiment through the state-owned media, he’ll have to follow it lest he risks coming out on the wrong side of history.
That’s part of the reason why the Kremlin stopped calling the protesters terrorists and putschists. First of course the Kremlin must quickly adapt to a new reality that is very fluid but indicates one thing: the Ukrainians want more Warsaw, less Moscow. But second is that there are quite a number of Russians who are very sympathetic to the Maidan. Those are a real threat to Putin.
Russia no longer is the Soviet Union. The Kremlin has worked hard on establishing popular legitimacy. So it can no longer resort to Soviet tactics, no invasion like in 1956 or 1968, no crackdown on large groups of political opponents. Putin like Yanukovich did too must wonder just how loyal “his” armed forces are.