Yes, V7 is based on Gen3F.

No, Gen3F/V7 does not currently work in any version of Poser. Some people have made attempts at making her work, but the results have not turned out very well as far as I'm aware.

You can use Gen1 and Gen2 and their characters in a limited capacity in Poser via a plug-in called D-SON. Gen3 currently does not work with D-SON for various reasons.

Some of the content for Gen2 might be compatible with Gen3 in D|S with various plug-ins. You'll need to ask in the D|S forum about that.

The development cycle for the Genesis figures has been about 1.5 to 2 years between each release. So based on that you should be able to expect Genesis 4/V8 in about the same time-frame.