Ok folks, here's how it works:
politician plays the role of "moderate Republican". The Bush presidency -- sorry folks -- is not moderate. HAving a closed-door meeting to discuss the upcoming energy policy with representatives of oil companies, and no other groups (I mean, come on, there are some rubber-stamp environmental groups you could invite just to appear moderate) present is pretty severe.
Jeffords' role in the tax cut discussions has not gone unnoticed, and, until he let this news surface, there was talk of retribrution among Republicans. If he goes to the Democratic party, he won't have to change his political views much (guys: coke and pepsi), and he'll be handsomely rewarded for his defection. His constituency will be very happy with the switch: he'll chair the Environment and Public Works committee (Public Works?! does anything say _pork barrel_ like Public Works?);
If he goes to the Democratic party, the Republicans already have a Democratic defector in mind (Zell Miller), so don't expect a revolution, just politics as usual.