2. Speaking from a historical point of view, the Democratic bounce was weak (Nate Silver said the average bounce was 7-8 points). It's just that the Republican bounce was even weaker.
3. Obama will not do as well as he did in 2008. Period. At the height of the convention bounce, he is doing only as well as he did then.
Considering these 2 points alone, you could actually argue that at the height of his convention bounce, he is falling just short of his 2008 margin (which was 7.3 points). Looking at all the national polls to come out after the convention, in order of the size of the Obama lead, it's IBD +2, Gallup +5, Reuters +5, Rasmussen +5 (+4 w/ leaners), CNN +6. Feel free to add in any national polls I'm missing.