With the talk of release of BV7 in 1080p...how much would it cost to upgrade the panel of BV9 (non full HD) to that in full 1080p HD? And is it worth it?

Oasis:

With the talk of release of BV7 in 1080p...how much would it cost to upgrade the panel of BV9 (non full HD) to that in full 1080p HD? And is it worth it?

I would spend the money on an excellent projector and screen - where one really needs Full HD. Having that on a 50" screen  is of marginal benefit. 

I don't think it is worth it. You may decide to upgrade it much later in the future though, as there is likely to be a much bigger leap in performance. Liken it to upgrading your computer every time there is a slight increase, just not worth it.

As soundproof says, the money would be much better spent on improving other things. Maybe if you're interested, improving the acoustics of the room?