In reply to JRNegus:
Or alternately, make like a porter and wear flip flops! I actually saw this when I was doing the route last October, they must have been carrying at least 25-30kg.
If you have a heavy pack I'd go with a reasonably lightweight 3-season boot, otherwise a hiking shoe would be fine. Warm clothing is very important, it gets very cold at night from around Manang onwards (assuming you're doing the circuit counter clockwise).