Whilst I'm NOT obsessed with "speed" - after all, not only is one limited by *your* connection with your ISP, but also with the links to the outer world, and I only changed from "b" mode Wi-Fi Router to the somewhat [potentially] faster "g" mode when the Linksys router failed to work - and I happened on a secondhand $200 Buffalo "g" on another expat site.
I'm now using a Belkin b/g -- but that's another story...
Anyway, what could be - potentially - more interesting to me is the a/b/g mode incorporated into a Wi-Fi router.
Months ago, I saw a very few models available in SSPo - but the price was considerably more than the b/g models -- ~$700-$800 as I recall.
That's still about 50% of the price I paid for my first wired-only Linksys - but too expensive to make an a/b/g wireless router "value for money" in my book.
Added to which, our family's two Lenovo T60p's that can handle all three Wi-Fi modes seldom use anything other than "wired" - made me back off "investing" in a tri-mode Wi-Fi router, especially since [as I understand it] if "a" mode is in use, then b/g connections to the router become unavailable - and I have several b/g computers and PC Cards at my home.
I'll hold off till a/b/g router prices fall & then hitch my hub into one of the wired ports to enable my 2 "b" mode Access Points & my 2 FON b/g Access Points in to handle all and any b/g signals around my home.