well I took a look at the official site and here are my thoughts about them:
Boyz:too bad they lost 6 boyz but will make it up for having their special weapons (I think), coting less, and looking better
Trukk:Looks totally kickass
Burnas:look like they are elites now but have improved looks
Lootas
on't know what they do but they sound like the new Flash Gitz or something
Tankbustas:also seem to be elites now but are cooler looking and come with squid bombs!
Killer Kan:looks like they are piloted by grots now but are still good
Deff Dreads:are the same as the old dreads except the name
Ghazghkull:Sounds awesome since you don't need 2000 pts (I think)
Weirdboy, Painboy, and Shokk gun:don't know how they will work but sound awesome nevertheless
Warbike:look menacing and come in a pack of three!
Now I have some questions about them
1.is the big gun battery still there?
2.are stikk bombs still useable?
3.will there still be trukk boyz?
4.will they keep red paint job?