It's been a while since I've watched ESB, so I just sat down and finally watched my bluray copy. I have to say that as a fan of all six films (they each have their flaws, but I try and love them anyways), the original Puppet is slightly underwhelming to me.
Some of the scenes with him are very well done, typically close up talking shots. Scenes where he is not the focal point are pretty disappointing though. It is hard to understand why, with as many things as they attempted to fix, they couldn't make Yoda look less like a floppy ragdoll during a lot of Lukes training.
I have a lot respect for the original films and film making techniques, but I do feel that it is perfectly acceptable to replace outdated effects...
For a lot of people, the replacement of the TPM puppet with the CGI version was a welcome change.
Without fear of being bashed (and please people, don't bash opinions on this) does anyone think that the Yoda in the OT could be replaced in a way that would improve the films? Keep in mind, this is assuming the CGI is done well and is well integrated not to stand out.