I am so glad there is a thread for this! Has anyone seen the R2 on Mustafar? It is the exact same figure, except this one makes noises. Big deal! Hasbro has been doing this for years. Don't get me wrong, i like them, but sometimes they are kind of silly. For instance, what was really the diffrence with the 2 Yodas from ROTS? A firing cannon?! That wasn't even in the movie.
Personally, I'm okay with multiple main characters with different action features and slightly different sculpts. That's just the way the modern line is. Let's face it, the days of there only being ONE Darth Vader, ONE Tatooine Luke, etc... like with the vintage line are LONG GONE. If the figure is different from any previous release then I do not consider it a rehash - it is a re-interpretation of the character in plastic.
I think the R2-D2 on Mustafar is a REHASH of the AOTC Saga Version, but I haven't really been able to compare the two figures to be 100% sure.
I think that in order to survive, the line will need rehashes to keep people who might be new to collecting Star Wars coming to the line. If you think back to the vintage line, while the vintage line didn't have multiple versions of say Tatooine Luke or Darth Vader, both characters were shipped on the cardbacks for all three movies. Being a kid at the time, I really only needed to buy a character again if I had broken one during play, otherwise, the first one I got was the only one.
Now that I'm an adult and I want a complete MOC collection, I think differently than when I was a kid and I turn around and buy the OTC release of the Endor Generals even though less than six months earlier I had just gotten them on Saga cards. It's all a matter of how you view collecting and what's important to your collection.
Sure, now, I view the multiple releases as pain to the wallet, but I could also stop at any time, no one forces me to collect SW toys.
I do like Valin's idea that the 2006/2007 lines should be sprinkled with re-releases of hard-to-find items - I definitely think that a Qui-Gon w/Eopie would be a welcome re-release. So would many of the other items on his list. I think if they return to the black card style then re-hashing figures with a few new or slightly altered figures thrown in every other wave will help keep the line going and encourage new people who were drawn to Star Wars by ROTS to continue collecting once the line turns its focus to the entire saga.