After a lot of effort I was finally able to get my new Verizon 6600 to work on WiFi. I tried a Skype call over WiFi and the quality sucked. It may have been the Starbucks I was at, or it may be something else.
I plan on more testing, but the ordeal to make this really cool device more useful was an exercise I really don't want to go through again.
First, SanDisk doesn't have drivers for the Windows Mobile 2003 Second Edition and has no plans on releasing them in the near future for their SDIO WLAN card. Bummer. That meant I had to buy a SocketCard, which does work on the WM2003SE platform. Since only Frys retails them in SoCal I had to drive to Orange County to get one of the four in the entire region. Once I got it, the software on the enclosed disc, dated September 2004, had to be updated from the Socket Web site...
Then it worked. WiFi was enabled. Now I have what I want. A fast, PDA Phone that can also work in the LAN as well as the WAN. Why Verizon didn't keep the WiFi chips inside the HTC Harrier is anyone's guess.