Hi,
Contrary to what a lot of people think, wheel weight isn't much more important than any other. It's pretty much bicycle + rider total weight that matters.
For accelerating (but not climbing hills and not maintaining a constant speed), the weight of tires and the rim count as double weight. But even if we consider heavy wheels versus light wheels (particularly when we don't count hub weight), these differences are still small and for must of us, losing a couple of pounds around the waist is a bigger change than having light wheels.
Unless you are racing, it really makes more sense IMHO to buy good quality durable wheels (with good bearings) instead of light wheels.
Cheers,
Charles