IF you base your argument on the EU stuff written about the 2-1B model (Star Wars Databank Entry), it says he's only 1.5m tall, making him under 5' feet tall and making the new one "correct" and the old one too tall.
I didn't even know the Databank listed its height, much less listing it wrong...
Then again, the Databank lists AT-AT's as 15 meters tall, but the films show them to be at least 20 meters tall... The same thing is going on with the Executor, which is listed a significantly less length than it actually is portrayed to be in the movies. Go figure.
Personally, and I agree it's like blue/brown coat arguments, I go with the ACTUAL size of the item... In this case the droid. 2-1B from ESB was anything but short, so that figure's accurate... The ROTS one may be smaller, but as Scott posted with the picture, the head at least is too small, and that leads me to believe the rest of the figure is.
The Kashyyyk Trooper still bothers me more... It's a clone for god's sake, so it shouldn't be shorter than another Clone like Gree or the others.
By the way, I picked these up tonight... 2-1B is kind of cool because the detailing is really nice on him, just such a shame he's dinky. That said, it seems to me that Anakin got quite a facelift over his previous figure! Way more than initially thought.
His entire torso is new, and ball/socket articulation now... His hips are ball/sockets of course, but the torso really is neat, and I must say, they sculpted it so his arms are more able to hold a saber 2-handed now. Far better than the Evolutions figure is able to, so really it's a major improvement. His eyes are blue, I find this odd since I thought he had sith eyes for this scenario, but whatever. It's a really great figure... I had a gripe on the elbow joints, but the torso fix really makes them more versatile. Good for Hasbro on that one... Well worth the re-purchase. He looks OUTSTANDING on the panning droid too, I must say.
Obi-Wan's nice, but mine's head won't stay on. He too seems to be mostly resculpted. The hands seem new, the head, the legs... The arms and body aren't I guess, but everything else seems to be. He's not as nice as Anakin, but he is quite nice for his duel on Mustafar.
2-1B is the waves weakest figure IMO... Which says a lot as, even short, he turned out to be a decent figure.