Frankly I thought the Spongebob anniversary special was better. And funnier. The Simpsons special wasn't bad at all, but I just felt it dragged here and there.
But I will say that Matt Groening hit the nail on the head when he said "Some people say they love Homer because Marge loves him, but I think people love Homer because Homer loves Marge." And that's very true. There's been some griping here about episodes that dwell on Homer and Marge's relationship, but it's that relationship that's the glue of the show. It's reassuring, it's touching, it smooths out the rough edges of the Simpsons' cold, cold world. It's been a stormy relationship at times, but at the core it's rock solid. I don't mean to change the subject, but the Homer and Marge relationship is the kind of relationship Cosmo and Wanda used to have on Fairly Odd Parents. And when that relationship fell apart, that show fell apart.
God forbid that should ever happen on The Simpsons.