As I said in the other thread that started this "debate," there is certainly a nostalgia factor in Disney that I cannot deny sways my opinion. I appreciate your thoughts and, until sha_lyn brought up the nostalgia factor in another thread, I didn't even think about that. And I certainly understand that the Mickey and Goofy of my youth are now forced to share the same stage with the Spongebob and Shrek.
However, I do have experience travelling with young kids as we've traveled on many of our past trips to WDW (and Sea World) with my young cousins (and therefore, I absolutely know who Dora the Explorer, Diego, and Krusty Krab are...and Rugrats is old...I was watching that one as a kid

...although I was more of a Rocko's Modern Life and Doug kid - but that's for another thread

). My one cousin who is close to 10, is, to me, the perfect age to experience Universal. While he may be past the Barney stage, I know that he'd still enjoy ET, the Animal Actors stage show, Shrek, Jimmy Neutron, Twister, Earthquake, Terminator, the Mummy, Men in Black, Jaws, Monster Make-up Show, etc. However, my 6yo cousin might enjoy the first four things on that list, but she'd be scared out of her mind with everything else. Give her 2 or 3 more years and we'll be all good, and, to me, all that she'll be missing out on is Barney.
I don't dispute that there are definitely things for kids at Universal. However, with ticket prices being the way they are these days, I feel that the best bet is to wait until they're 9 or 10.