Hello,
I have had the FiOS service in Natick, MA for over two weeks now, and while I'm very happy with the speed, I'm quite frustrated with trying to get it to work with my Linksys routers.
I have tried 3 different Linksys routers (BEFSX41, WRT54G, and WRV54G) using near 10 different firmware versions on each (just to make sure I'm not crazy).