A battle sequence between clones and droids on that scale with those shots would be near impossible to do practically.
Yes, we should thank it for sucking all believability and intensity from it as well. It was a cg wank fest; i didnt' give a damn who or what was blowing up-- AND that my freind is unfortunate! Atleast, I cared about those bastard-ass ewoks!
Now, the rancor scene could use some work, but with a few touch ups, good as new! I can't imagine it any other way, besides.
Personally, growing up weened on the action/scifi films of the late 80s/ early 90s and with recent revisits to these films and the old school special effects school they represent, noticable CG completely takes me out of a film. It's true, there were lots of shoddy special effects jobs in those days, but there are plenty that look damn good still and atleast they benefit from being constructed of actual physical materials!
My utmost pet peeve is the replacement of classic man-in-suit, costumes, and prosthetics for a cg replacement. For the love of god, is it really that hard to make a storm trooper outfit these days?
I fear cg will become more and more commonplace with each and every film that utilizes it; the trend doesn't exactly encourage people to learn the old way of doing things, which is a shame.
Jurassic park and LOTR: fotr were good/desirable uses of the medium. That is to say, if all movies pulled it off so well, i'd have no problem with CG. They still had a few hiccups, but you can't expect perfection.
That said..
list of movies from recent memory where CG completely ruined the mood:
Spider man 2--hmm, yeah, paste the faces on and they won't notice the difference between a real person and a strangely warped, blurry rendition of said character. Since this cg malady affected nearly every action scene, i=not very pleased.
matrix 2-erm..afformentioned blurry rubber man effect. (see above)
lotr 2 & 3-i'm being a little harsh here, but while i thought fotr did an excellent job with its cg, the little hobbits in treebeards hands' looked especially bad, and rotk pelenor fields(?) battle was plagued by a tried and true *yawn* worthy cg spectacle of bad direction(helm's deep was the first sign of this illness)--horde vs horde style-- to say nothing of legolas surfing down an oliphaunt's nose!