Yeah, that code really makes no sense, since neither float should actually happen.
NOT that there is ANY reason for #header to even exist in 99.99% of the sites people slap that extra div in there.
Of course, you also have to ask WHAT IS that content, and IS there a semantic tag for it, since it could well be inappropriate for #logo or #title to actually be DIV when a heading tag, paragraph tag, or list tag may in fact be more suited to the job -- heck could be it should be a SMALL tag inside a H1 just based on the names you used.
Though, are you asking about float CLEARING or float WRAPPING? If you want #header to wrap that's easy enough to do -- if you always have the same element after those like say, your menu, just put clear:both on that.
In either case, I always advise AGAINST presentational nonsense like clearing div, clearfix, and the whole host of other bloat you see people using all the time -- usually there are MORE than enough tags in there to hook SOMETHING with the desired behavior without slapping extra elements or even classes in there.
Really, you want to avoid divvitus, ease up on the number of unnecessary div and use semantic markup saying what things ARE. Like say... a page HEADING. Heading? Don't we have tags for that?