The anti-global-warming measure most commonly advocated as needing to be done immediately (or sooner) is reduction in fossil-fuel use. So far as I can see, this isn't politically convenient for anybody.

Beyond that: sure, it's worth distinguishing between "do experts agree that AGW is real?" and "do experts agree that AGW is real and likely to produce more than a 2degC rise over the next 50 years?" and "do experts agree that we need to cut our CO2 emissions substantially if the result isn't going to cause vast amounts of suffering and expense and inconvenience and death?" and "do experts all predict exactly the same best-guess curve for temperatures over the next 50 years?" and all the other questions that one might ask.

Eliezer's original nomination of global warming as something not to try to work out on one's own was from back in 2007, and slicedtoad's claim that "experts don't agree" is from yesterday. There's been a shift, over the years, in the commonest "skeptical" position on global warming (and hence in what question we might want to ask) from "it probably isn't happening" to "well, of course it's happening, everyone knows that, but it probably isn't our fault" to "well, of course it's happening and it's our fault, everyone knows that, but it probably won't be that bad" to "well, of course it's happening, it's our fault, and it's likely to be really bad, everyone knows that, but major cuts in fossil fuel use probably aren't the best way to address it". I think we're in the middle of the transition between the last two right now. My guess is that in another 5-10 years it may have switched again to "well, of course it's happening, it's our fault, and it's likely to be really bad, and the answer would have been to cut fossil-fuel use, but it's too late now so we might as well give up" which I've actually seen (I think here on LW, but it might have been over on Hacker News or somewhere of the kind).

In 2007, a little digging suggests that the transition from "probably not happening" to "probably not our fault" was in progress, so perhaps the question to look at is "are human activities causing a non-negligible increase in global temperature?". On that question, I think it's fair to say that "experts agree".

Right now, though, the question is probably "how bad will it be if we continue with business as usual, and what should we do about it?". My impression is that to the first part the experts all give answers of the form "we don't know exactly, but here's a crude probability distribution over outcomes"[1] and their distributions overlap a lot and basically all say at least "probably pretty bad", so I'm pretty comfortable saying that "experts agree" although I might prefer to qualify it a little.

As for "what should we do about it?", I'm not sure who would even count as an expert on that. I'd guess a solid majority of climate scientists would say we ought to reduce CO2 emissions, but maybe the nearest thing we have to experts on this question would be politicians or economists or engineers or something. I wouldn't want to make any claim about whether and how far "experts agree" on this question without first making sure we're all talking about roughly the same experts.

[1] Though they don't usually put it that way, and in particular despite my language they usually don't attach actual probabilities to the outcomes.