Red Velvet is the new rookie girl group of the SM, the members are from SMROOKIES. Here is the teaser if you don't have hear it yet. 

I just heard the teaser, i can't say if I like it or not, 'cause you can appreciate their voices well.

but this is a thing i don't like: the unjustified hate. 

why this 'fans' hate them so much? they have not even debuted! the girls are so pretty and they sing so good! (i have heard SeulGi and she sings wonderfully) one reason may be jealousy: this cute girls are friends with their 'oppa' - i can assure you this would not happen if it was a boy-group. I can feel the SM, having the most popular boy band in Korea, wants to do the same with a girl group. First, we have to wait for the Happiness MV (Red Velvet debut song) and we will see. 

And, the f(x) theme... SM is going down lately, eh? 

And they can't be a little more original with their songs? Overdose, Mr. Mr, Red Light sound a little alike, with this electro sound and stuff. I like the songs but, they have work a little more on their major groups.

sorry for my bad english, i'm studying!