Seriously people, I am also ultra disappointed. I used to be a very big fan of the series, having watched the episodes twice and being present on this site from the start.To be honest, I think that this series ended on such a bad note that it made it one of the worst series I've ever seen.

But let's not be so negative. I have some slightly positive points to make and some clearly positive ones:
For me the disappointment was lessened by the fact that as the episodes progressed, more and more questions were left unanswered and instead of logically wrapping things up, more inexplicable and illogical things kept happening. This made me understand that the writers were seriously messing up and couldnt keep up. It was apparent that there wasnt any master plan behind who red john is from the beginning, and that's why the clues simply didnt add up. So I was set up for disappointment and I took it fine.

Secondly it's just a TV series and of course there wasn't any guarantee it would be great. For me, not being able to keep a coherent and logical course of actions totally destroyed the feeling I had, but it's OK :) Life goes on.

Now on a more positive note, there are extremely good TV series out there, very well thought out and with crazy drama built in. Some of them come to mind:
Breaking Bad (absolutely top notch)
Game of Thrones (top notch)
and even 24 (very good - at least some seasons)

So, instead of swearing and blacklisting Heller (which is an OK thing to do) we can move on. There is still a 0.00001% chance that both the promo for the 6x08 and the leaked episode are totally fake, and a HUGE new episode comes out tomorrow that explains everything and connects all the dots like magic, providing an exciting and dramatic-surprising finale with a suspect that noone ever suspected and who, when presented with the revelations, will make us walk and drink wine in Heller's name, while having the biggest 'aha' moments of our lives.
But even if not, don't despair :)
Cya!