Haha, do some research?
Hrmm, lets see, what research could I do...
Oh yeah, there is that wifi antenna up on my house that is beaming to a tower about 15 miles away. I get less than 2-3ms when I ping the gateway at the tower. Worst case scenario I get 10ms.
And I just pinged my router and I'm a few rooms away. 1ms.
If you really want to continue this argument I will get real data and send it your way.
Don't compare a WISP + Tower to home WLAN with that weak WiFi board and poor antenna the Wii has.
I get 5ms from my ISP on my connection on ethernet. On my laptop, it get 7ms. That's 2ms more. And my laptop has a large antenna based on the size of the screen.
Anyone who has tried to move their Wii around a large house know the range on it is very limited. Most people say it's somewhere around 30 feet with a normal 802.11g router.
I can personally vouch that I have both a Wii and a DS in my place right now that grab WiFi from about 700 feet away with a WRT54g with a single 7dbi antenna attached. And it goes through about 6 or 7 walls, some metal.
By the way, you say when you're a floor away you imply that having a LAN adapter will help that situation. I don't know about you, but if my Wii was in the living room which is a floor away from my router I'd have to run a several hundred foot ethernet cable out of the computer room, through the game room, down the stairs, through the kitchen, and into the living room. The cost of the cable + the LAN adapter far exceeds buying a cheap 7dbi or even 9dbi antenna which could easily boost the signal to way more than adequate levels. Even without the antenna there are lots of things you can do. Reposition your router, reposition the Wii, build/buy a parabolic reflector for the router antennas, etc.
2ms extra would not be noticeable to anyone especially on a client to client connection. In fact, I'd be willing to bet that 99.9999% of people won't be able to differentiate between +20/-20ms.