As I noted in a thread yesterday, Pogue is a big fan (raved in last weeks NYT Circuits), and he hates when stuff isn't Mac-compatible.
Pogue notes that the phones will work w/any open WiFi router, but if you want security, you should use the free-after-rebate router. Bonus is that the router security setup is as simple as could be.
One extremely cool feature that I remembered later is that calls home are free from ANYWHERE IN THE WORLD w/an open hotspot.