there was an interview with director jerry o' flaherty the director of the upcoming thundercats movie posted on youtube. scheduled in 2010, according to IMDB, he has stated for the record that the film version will NOT be live-action, but CGI.

http://www.youtube.com/watch?v=ixLojWJ3z-M

i am dissapointed, given the fact that with a good cast and good storyline this film was destined to be a hit. as a fan of thundercats, the idea of a motion picture version sounded good, but the fact that they are not going to use actors, is dissapointing. i understand that casting actors for certain characters can be off-putting, especially if they are the wrong choices but with thundercats, this was an ideal opportunity to cast well known actors and actresses as lion-o, cheetara, panthro, tygra and of which would've worked well, if the cast was indeed right

That would depend on the makeup and costumes. If they sacrificed realism,
"Thundercats" could have just looked silly with real actors. Remember the
first three "Teenage Mutant Ninja Turtles" movies? It worked for them (I
especially like the first film), but TMNT was a comedy-adventure cartoon to
begin with. For a straight adventure like "Thundercats," animation (even CGI)
is probably a better way to go (in my opinion).

That would depend on the makeup and costumes. If they sacrificed realism,
"Thundercats" could have just looked silly with real actors. Remember the
first three "Teenage Mutant Ninja Turtles" movies? It worked for them (I
especially like the first film), but TMNT was a comedy-adventure cartoon to
begin with. For a straight adventure like "Thundercats," animation (even CGI)
is probably a better way to go (in my opinion).

i don't want the director to do what the director of alvin and the chipmunks did by overhauling their image and make the characters look horrible. of course, we all remembered masters of the universe- the film based on the he-man cartoon starring dolph lundgren and courtney cox, which was live-action and totally diabolical, back in the 80s. but with thundercats, the characters themselves are cats in human form and so i don't see why they cannot cast actual actors and have them in costume and wearing make-up.
providing that, as you rightly said, looks-wise the look and design of the characters are good for a feature length film and that they all bear a resemblance to the thundercats cartoon series.

btw, teenage mustant ninja turtles was originally a comic book itself before their translation on TV in 1985.

feel free to agree or disagree with my choices. :)

lion-o- brandon routh (superman returns)
tygra- hugh jackman (wolverine in the x-men trilogy) or aaron eckhart (paycheck, thank you for not smoking and the black dahlia)
cheetara- either charlize theron (monster, aeon flux), kristina loken (terminator 3) or rebecca romijin (ugly betty, x-men)
panthro- terry crews (everybody hates chris)
wily kit- dakota fanning (man on fire, hide and seek, i am sam, uptown girls, charlottes web)
wily kat- jonathan lipnicki (jerry maguire) or vincent martella (everybody hates chris)
jaga- sir sean connery (league of extraordinary gentlemen)
lynx-o- patrick stewart (x-men), sir ian mckellan (x-men, lord of the rings) or terrance stamp (superman 2)
snarf- CGI (get someone guy to do the voice of him)
mumra- christopher lee (dracula, lord of the rings, star wars 2: attack of the clones)
slithe- andy serkis (king kong, lord of the rings trilogy)
jackalman- jim carrey (the mask, the grinch) or steve buschemi (resevoir dogs, desperado, fargo)
vultureman- guy pierce (memento)