Thunder, Thunder, Thundercats!! HO!!!
Most of the original group is shown here, Lion-O, Tigra, Cheetara, Wiley Kit & Kat, even Snarf. The notable absence is Panthro, but there wasn't a great deal of tech in this trailer, so I can let that go. I saw some of the publicity stills released (which included Panthro) and I liked the updated version of the group. Seeing them in action, re-enforced my appreciation. Some of the old villains also make an appearance: Sabertooth, Slythe (looking more decidedly blue, but given that part of the trailer is taking place at night/dusk, that could just be a shading thing), and of course, Mumm-Ra, the Ever-Living!!!
Just the small bit of the transformation shown is enough to make me want to watch this show! And it looks like they've upped his power since even his transformation is now potentially lethal!
I'm also liking the epic scope of the trailer, but I do have some misgivings. Part of the appeal of the original series was having the ThunderCats learn to adapt to a new and strange world. Learning to work with the indigenous people and dealing with the natural threats of that world. The dialogue here puts 3rd Earth as either the origin world of the ThunderCats or a well-established planet in the ThunderCat empire. Which in my eyes, would diminish the show somewhat.
Still this is just a trailer, so over speculation on the storyline is premature at best and at worst ill-advised. There's a great deal of amazing work here, and unlike other remakes of 80s cartoons (He-Man, anyone?), this one stands a solid chance of surviving. Surprisingly enough, I'm looking forward to seeing this!