I wouldn't have have SF #1. Davis and Iupati are basically better versions of Giacomini and Carpenter. Like Seattle, SF is built around elite level road graders who struggle in protection- Iupati and Davis are the epitome of that. Bowman was a great pick. It's easily top five but I think I'd put Seattle ahead of them, and I'd consider the Bengals for #1 as well (Atkins probably goes #1 overall in a 2010 re-draft, plus Dunlap/Gresham are good players as well).
Seattle's draft already has 3 pro-bowlers with two more that have pro-bowl talent (Tate, Thurmond). McCoy has turned out very well for a 6th rounder, too bad he'll miss this next season. They should probably be #1, but there are a few other teams that make a decent argument. I don't think SF is one of those teams. Their grade is highly inflated by the perception of their O-line. Most people are under the impression that SF has an elite line and Seattle has a bad one, but what they fail to realize is that Seattle's line statistically played on par with SFs last season and actually outperformed them in the head to head matchups. I think the inflated perception of SF's line had a trickle down effect on how the 49ers were ranked here.