I notice its an old thread. Between, Tarneit, Wyndham Vale and Trugannina, I would rank them ( 1,2,3) in that order.
The train stations are ready and train service is due to commence early 2015.
What many people are not aware of is that even though its V/Line , the peak frequency is pretty decent and the fare will be just your normal Zone 2 (myki) fare and much less stops on the way to city.
What I like for Tarneit most (along these three) is that it provides you with easy access to City via multiple routes, to Airport/ northern suburbs , very close to Billion dollar upgrade Pacific Werribee Shopping Centre ( new Village Cinema, Myers, Target etc).
Tarneit also has got better access to better and established schools in the area (Hoppers Crossing/Werribee) and medical centres. The relatively more established areas of Tarneit between Heaths and Hogans Road (still less than 10 yrs old houses) , I have seen the properties gets tenanted within a week, it falls in school zones of a number of established schools and even good private/catholic schools near by and a new coles shopping centre for Tarneit West, A very short walk to the Werribee River. Compared to Point Cook, no peak time traffic issues. Good potential IMO.
A brand new shopping centre is also coming up next to Tarneit Train Station. Plenty of Coles , Woolies, Aldis near by. If you last visited Tarneit 3-4 years ago, you may not recognize it as the same suburb.