I get this question a lot - and being a public company of course I cannot share any confidential information beyond what has been published. Last week Wireless Week published an interview with Pieter Knook in which you can find a few interesting datapoints:
To read the full article go to Wireless Week CTIA Show Daily archives http://e-ditionsbyfry.com/ActiveMagazine/welcome/tww/daily070401.asp then open Day 1 edition, go to Page 54