There is a presidential popularity poll over at Rasmussen. It looks about right to me: Obama's positives are holding up, maybe off just a little, his negatives slowly rising.
About 20% of the electorate firmly supports his agenda, pretty much whatever it costs. Another 20% supports it generally, but worries about going too far overboard. 20% don't feel strongly, but wish any new guy well. What's interesting is that last 40%, who one might expect would be strongly against him from the start, having voted for the other guy. Only a little over 10% of the populace has been implacably against him from the start. You can probably knock a few points off that 10 for those who gave him a clean slate on election day but didn't like his transition decisions, and add some points back on for conservatives whose well-wishing might have been a bit grudging.
It's worth noting the trend right here, because it's going to be spun that his nefarious opponents never gave him a chance, and marshaled all their forces to oppose dear Barack for nonsubstantive reasons like racism, believing lies about him, etc. Witness it now: he was given a chance, and is already squandering it by his own actions.