He has a pretty consistent voting record on the far left, but I wonder if that was not just positioning himself for a post-Bush run...
On the whole, his cabinet and other nominations are fairly centrist, or balanced. (Leon Panetta at CIA is a concern to me, but that is another post.)
While it is true that Obama is moving rapidly on several issues that are favorites of the Left (Abortion, Gitmo, "torture"), he is taking it easy on other areas (card check, tax increases), and I think this is a result of the mainstream advisers he has surrounded himself with. (Whether this continues remains to be seen.)
It seems to me that this is causing consternation on the Left. This is particularly true among those members of Congress who cut their teeth back when the GOP had decided to be the Anti-Clinton party (yes, they did start it), and then spent the next 8 years being anti-Bush. Now that they are in power, they want to do things their way, now.
This is, I think, the reason for the much quoted Majority Leader Reid statement, "I do not work for Barack Obama."*
Maybe this is who Obama was really addressing in his inaugural addressl when he said,
On this day, we come to proclaim an end to the petty grievances and false promises, the recriminations and worn-out dogmas that for far too long have strangled our politics. We remain a young nation, but in the words of Scripture, the time has come to set aside childish things.
*Granted, the statement is couched in some constitutional structure language, but it seems to me that there was a signal being sent.