It is lighter. Its also more variable. I wish it were a little tighter at low speeds. I do understand the complaints about the '05-'10 models--at times I used to feel it was too heavy and required too much effort--but I do think they went a little too far in the other direction.
However, it is still nowhere near as light as the Sienna. At highway speeds in particular there is a big difference. I drove a Sienna LE for several hundred miles as a rental (and before anyone complains, this was a brand new vehicle that only had 400 miles on it) and the steering was super light and required a lot of course correction at highway speeds. I do not find that with my 11 Odyssey at all.
I agree with this ... steering is disappointingly lighter (seems to be the trend in most cars these days --- the 5-series we recently got suffers from the same trait) .... but turning radius, handling, braking, and ride quality are significantly improved ... I am accepting of this trade off.