The Virtua Tennis series is pretty good.
Virtua Tennis 2009 has recently come out but Virtua Tennis 3 (last years) is worth getting, cheaply too.
It Depnds, if you are tennis fan, Follow the sport then Virtua is the worst tennis game ever made.
I hate the way you playing on a pool table, training in space, under the sea stc. The Career mode does not even loosely resmeble a tennis season.
For a Casual tennis fan and a decent gamer then Virtua tennis is good, because its gameplay engine is very good, nothing else though.
My Personal Favorite game is Tennis Elbow 2009, its a low spec pc game
http://www.managames.com/tennis/game_en.html
Its got a full ranking system, a real ATP tour were you play the real touranments at all series levels.
Its realistic to the point on your first tour you may not be able to enter a grand slam depending on your perfomance.
100 + real players with acurate ability levels.
The Game mechanics are complex and finicky but you will adjust and enjoy it
So if you follow tennis - Tennis Elbow 2009
If you watch wimbledon and get a tennis bugt for a few days then Virtua Tennis