At the moment I've only played it once but here's what I think...
The positives: One thing that I love about the game is its calendar, unlike its main competitor Topspin, Virtua Tennis incorporates much more things into the World Tour and the calender year is much more interesting, the plethora of famous top players is also a fantastic attribute to the game. The gameplay is also much smoother unlike the clunky style of Topspin. The fast paced tennis play, though unrealistic as such, is fun to play and watch.
The negatives: Though I've never been amazed by the character creation possibilities in tennis games I think that Virtua Tennis 2009 has taken a huge step back in their character creations, most looking rather similar or plain fake! Topspin on the other hand makes characters look more realistic and diverse. As a statistics fanatic I like to see how I'm playing however Virtua Tennis provides much less information compared to Topspin.
Graphics: 7.5 (Weak on the character creation front and in my opinion less realistic compared to Topspin)
Characters: 8.5 (A plethora of top players to chose from)
Gameplay: 8 (Though fun to play and watch it is a bit unrealistic as everything is so fast paced)
Game Design: 8 (The pages looks sleek besides the loading sequences)
Longevity: 7.5 (I think the game has a lot of potential for a lot of hours of fun but the weak character creation front is a bit annoying as it provides the main section of the game)
Overall: 39.5/50 (79%)
This score is Ok, I'm quite a nice marker so not making the 80's for a tennis game (I'm a tennis fanatic) isn't a great score. The character creation reminds me of the very old games that cost £5's at Tesco's but the sleek gameplay, amazing cast of players and well developed calender system is a plus point, if the character creation was better it would score way in the 90's.