51 is great but that's not what most people are getting. I'm getting 42 - 44 mpg. Right in line with the EPA estimate. I use to drive a prius and could get 52+ so I know how to drive a hybrid. I don't hypermile but I also don't ride the gas and coast as much as possible.41 US mpg is very good for a Camry, but the 51 US mpg we've been getting in our CT is better. Plus, in Canada the Camry Hybrid actually costs $400 more than the CT.
Basically what people are saying is that if the Camry hybrid can get 41 with the 2.5 engine then you should be able to do better if you put that same engine in the CT (lighter, more aerodynamic, etc). You'll probably be able to get 42 - 44 mpg with that engine in the CT.
I would love to see that engine in a CT. It would be faster than an IS 250 and get 40+ mpg. The CT300h or whatever we want to call it would destroy the competition. That's probably why it won't happen. Makes too much sense to us.