*takes deep breath* Beware - this is gonna be a long one
First off I want to say that I love the new show to pieces. I loved the old show in it's day but I have to say I like the new one better. They are treating it much more intelligently this time around (better plot, better characterization, better bad guys etc). Usually I say that the 80's version appeals to the fan I was when I was a kid and that TMNT 2K3 is best for the fan I am now.
I like the new character designs. Initially they reminded me of the old first-run action figures (you know, before "Sewer surfing Michealangelo" and so forth). If you look really closely each Turtle is actually a different shade of green. I like how they give it that individual touch (unlike the old show where the only difference was the bandana colour and the letter on their belt buckle).
I like how Splinter has a bit of attitude! You can tell where the guys get some of their bantering ways from now. And Shredder is actually evil, Evil.
And I'm probably happiest of all as a Leo fan-girl. He has always been my favorite but in the old series he often came in last place as far as time-in-the-Turtle-spotlight. He's more than making up for it now! Leo is THE Turtle!
I also love how the new show fits in little "in-jokes" and pop culture references. There is the aforementioned "A very wise frog once said....." quote and then there is the following scene. It comes from part three of the Secret Origins storyline.
April and Casey are in the BattleShell wondering what the heck is going on inside the TCRI building. They know the Turtles are inside but the problem is the army has surronded the building.
April decides "well, they [the army] won't talk to us but they might talk to a TV news reporter." And she comes out of the back of the van wearing this yellowjumpsuit which, as Casey put it, "Looks great! If you're supposed to be handling toxic waste that is."
At the end of the ep, once they are again reunite with the Turtles, Leo teases her, asking if she's now a TV reporter. She scoffs and goes "Yeah right. Maybe in a previous life."
Plus, there is a reference to Krang a little earlier in the ep as well.