Some would say that if you're working nights and weekends, that's a sign you need a better iterative development methodology (like agile).
My experience has been contrary to yours. Having everyone own the code means that people don't throw bugs over the fence to the only dev that is working with that bit (who happens to be on vacation for three weeks); instead, they fix the damn bug themselves and, if they're not confident about the fix, send a note to the guy that knows the most about that code.
I don't think Agile is a silver bullet. I think iterative development with frequent testing is generally a good thing, whether it's in the form of agile, rup, whatever. Doesn't have to be Agile.