A few weeks ago, we used some money from our savings account to by a Dyson vacuum. (WM had them on sale plus a $100 gift card!). Oh my gosh. The first night we actually fought over who got to use it first. It sucked up so much junk off the floor AFTER sweeping it, I started to gag a little bit. We don't even have carpet.
I try to vacuum the floors 2-3 times a week and it picks up such a large amount every time, i'd be frightened to space it out any more.
Bottom line, if you have the means to get a Dyson, do it. You won't be sorry.