They are very similar cards.
The Elsa offer gives you a seperate Video Module, and you also get an Optimized version of Giants just for their card. In addition, you also get a DVD player with it, and a few other lil extra goodies in the software bundle.
Hope that helps ya.
As for the Hercules, I know lots of rumours have been going around, and who knows in the end they may be true, but as far as I have been able to find out, it's not discontinued.
They are sending out their next shipment in the 1st week of August.
**Edit typos what else**