Sony 70-400 G2 vs G Alpha

[R3d]

Sony will be releasing its "new" 70-400 lens soon, and I was curious if anyone knew of any actual differences between this lens and the old one? I just bought an a99, and haven't had the chance to use my 70-400 on it yet, but was wondering how much of a difference the G2 (being designed for full frame) would make as far as image quality in comparison to the slightly older lens.

New one:

Sony 70-400mm f/4-5.6 G2 Telephoto Zoom Lens SAL70400G2 B&H

Old lens that I currently own:

Sony 70-400mm f/4-5.6 G Alpha A-Mount Telephoto Zoom SAL70400G

I was thinking about selling my current one in favor of the new one, but I may not bother with it at all if there's no actual difference in glass, and it doesn't really look like there is.

 

[dxqcanada]

Much feedback from users (in Europe/Asia) who have tried the G2 ... it is an improvement, enough to cause many to upgrade.
today try the new SAL70-400 SSM G II - Dyxum forums - Page 1
Sony*AF 70-400 F4-5.6 G SSM II lens reviews

I have been waiting for used G1's to come on the market (as the G2 is out of my reach, though I would love to get one).

 

[R3d]

Looks like the AF is the only really serious change to it. The optics seem the same except for the coatings apparently. I may hang on to my G1 for a little while longer.

 

[Kolia]

G2 has circular aperture blades. The G has a reputation for weird bokeh.