I'd really like for the new show to be completely unconnected to "Friendship is Magic" in every way; new story, new world, new animation style. But, I want a mix of some new characters... and a lot of characters from previous generations (including Gen 4!) re-imagined with updated looks and personality. Why? Because that's the way MLP has always been. None of the Mane 6 are original to FIM, they were all borrowed from previous generations. Some were drastically different from their predecessors, others were an amalgamation of various ponies that had come before (like Pinkie Pie being a combination of G3 Pinkie and G1 Surprise). It would also be a great way for Hasbro to bring back some fan-favorite G1 and G3 characters. Personally, I'd love to see a new Sunny Daze make an appearance in the Gen 5 show.
Also, for everyone who is complaining about Twilight being an earth pony instead of unicorn/alicorn, remember that Fluttershy was a pink earth pony in G3 and an earth pony with a completely different name in G1! Change is nothing new to MLP; it's like the Doctor Who fandom -- you just have to give the new generation a chance.
Mostly, I'm just excited to see what the new toys will be like. "Friendship is Magic" was a great show which I loved a lot, but most of the toys stink compared to previous generations.