The preorders are now open at BHphoto, Adorama, Amazon, FotoErhardt, Fotokoch, WexUK.
SonyAlphaBlog reviewed the new lens and concluded:
The Tamron 70-180mm F2.8 Di III VC VXD G2 (1500 euros) is a clear step up compared to the Tamron 70-180mm F2.8 Di III VXD (1200 euros) with improved sharpness, improved ergonomics and build quality. Unfortunately the AF has not drastically improved and is still well behind the Sony GM especially for sports
Dustin Abbott also tested the lens and concluded:
So is it worth buying? From a value perspective, absolutely. It’s not quite at the GM II level on any level other than sharpness, but it’s not far behind in most categories. I would also say that it is worth upgrading if you can get decent value from your G1 lens. The Tamron 70-180mm G2 is a lot of lens for the $1299 USD price point, and the range of improvements is pretty much across the board. Sony shooters are once again the winner, as we are getting ever improving options from Sony and the various third parties who develop for E-mount.