I sat on the 2013 at the NY International Motorcycle Show this past weekend. I'm 5'7" if I eat my Wheaties and don't like tiptoeing. The 09-12 feels a bit too tall to me. I was not unduly put out by the 13, so I'd guess the seat is in fact narrower.
I don't need to flatfoot a bike to be comfortable, but getting one foot down with the ball of the other one on the ground is about as far as I want to go when I've got $12000 worth of motorcycle that might get dropped under me. The real world has sand and gravel on the roads and if you've ever slipped on some trying to support a bike you know what a PITA it can be.
The 636 lets me do this. I couldn't quite get there with the older bike. The GSXR, on the other hand, fits me like a glove... if I fully stretch my legs out I can get both heels down. Thing is, GSXRs are just so... squidly.
(j/k... they're fine bikes)