There's always been a reasonable amount of similarity between the concepts of SNSD and Kara.
As a Sone, Jessica is my favorite idol of all entertainers, male or female, asian or otherwise, but I don't think she pulled off the look very well; on the other hand, I don't think Gyuri pulled off the look very well either. The outfit colors make it very hard to pull off. I can't think of anyone that can use the outfit and make it look good.
But on the topic of their similar concepts, notice the cute concepts were both relatively close, then their style evolved and matured quite a bit at the same time, yet within a few months time they both revealed a cheerleader concept. They're friends after all, maybe the manager's talk? Or maybe it's a business thing, no clue.