Indo-European dispersal

What are the latest theories about the dispersal of Indo-
European speakers?

I have just re-read an the article by Tamaz Gamkrelidze and
V. V. Ivanov (1990) which postulates that Eastern Anatolia
was the dispersal point/'homeland' of the Indo-European
languages, rather than an area in Southern Ukraine/Russia
favoured by many other theorists.

Gamkrelidze and Ivanov's theory may account for the well-
documented historical contacts between IE and the Kartvelian
languages (Georgian, Mingrelian, Laz, and Svan).

What role might the theory of Black Sea inundation have
played in language dispersal?

Geoff Powers