No, Terracoin is not dead. Right now it's *crazy* slow which was due to an upgrade where the way the difficulty was calculated was changed so that it didn't fluctuate so rapidly. Some thought this idea was good (I didn't personally- I think fast difficulty adjustments are the way to go) and it was changed.
Well now of course we see the result of that- we're stuck waiting around for an insanely high difficulty to drop. Not so genius after all.
What we need is to fix the difficulty adjustment so we prevent the exploit Sunny King pointed out while also preventing slowing the chain to a standstill because of having to churn through such a high difficulty.
A message has already been sent to the Dev's so we'll see how they sort it out.
In the mean time- pump and dumpers, there are still plenty of other Alt-Coins to try and make a fortune on so have at it.
Try and thing it though a bit more next time or stick to your guns about what you think is right....or its not going to look good
also don't release any information about an exploit even existing, only if someone else releases then you can say yeah we knew and fixed that x years ago!!!!