How important is the wheelset in a road bike?

I would like to buy a new road racing bike,should I invest in a good (expensive) wheelset although this would mean that I will have to spend less on other parts (besides the frame).
Is there a different, beside weight, between a normal price wheelset

There was a discussion on forums.roadbikereview.com about this specific topic. Most of the people in that conversation recommended going with a handbuilt set of wheels if you can afford it, from a good wheelbuilder (like oddsandendos.com). Handbuilt

Competitive Cyclist Reviews the Fulcrum Racing Zero Wheelset

Competitive Cyclist's review of the Fulcrum Racing Zero Wheelset. Fulcrum Racing Zero is amazingly smooth, yet laterally stiff enough to ...

New Syncros Marathon and All mountain wheelsets

  First up a set of carbon wheels that while expensive are much cheaper than many such wheelsets, followed by an all mountain wheelset for the more demanding rider.   The rear comes in a 135 x 100mm or 150 x 12mm option and is ready equipped with four “Heavy Duty” bearings plus two bearings in the FH. This handbuilt wheelset is laced with 32 DT spokes using a strong, reliable 3 cross pattern. This new fast and strong freeride wheelset is built with one of the lightest and stiffest FR-rims on the market. Syncros are renowned for building components that can take a bit more abuse than standard lightweight equipment yet are still relatively lightweight.   The front wheel comes with a 20mm true axle and four high quality bearings.   They have a strong history in mountain biking so when they bring out a new product it is always worth taking note.