I am pretty certain this show is dead.
Reasons:
1. It's been nearly 2 years without TARA, it can't keep going with such huge breaks between seasons. We've already had a 1 year gap between TARA3 and TARA4
2. Allan Wu seems to be focusing on China Rush
3. It's obvious the show has budget problems, evident by the decline in production quality and the incredible amount of product placements that plague the show. This is ironic considering the rise in TARA's rating over the seasons.
Yep, the show for me is dead, just like it's quality. I don't mind product placement as long as it keeps a show running, but this is waaaay too much and not worth it. TAR fans in Asia, Rejoice! There are now more asian versions of TAR being produced. Only time will tell how good they are.
TARAsia rest in peace, you've had a good run, but then had to destroy yourself (TARA3) and even after a respectable attempt to recover (TARA4), it wasn't enough. Out with the old and in with the new.
Then again...
I may be wrong. Who knows? the show may return in 2012 or 2013 and it might blow our minds. here's to hoping that happens.