Second hand at a E3 thread at this site or AVS, supposedly from a Nintendo representative. I'll see it I can dig up a source for you.
Edit - Looks like what I read was from Anthony1 (A once familiar face around here before being banned) at the AVS forums. No source was provided and a Google search doesn't bring up anything relevant.
Here is an interview that was widely circulated that discusses the range of the controller (And also prefaces it by mentioning how the controller is tied to the console and can't be taken everywhere and used, a fact that has been widely circulated online). And while they don't state a concrete number for the range or compare it with the current Wiimote, it's certainly safe to infer from this interview that the range is somewhat limited.
http://www.officialnintendomagazine....troller-range/
And a quote from a Nintendo executive about the controller that might be of interest.
"The thought is you'll be playing in the same room that the base console is in." - Nintendo's Katsuya Eguchi
http://kotaku.com/5811558/nintendo-d...o-the-bathroom