Now that it has aired let's hear your thoughts...
I thought it was brilliant, not as edgy as family guy normally is but edgier than Simpsons norm. Clearly Seth had to tone it down a bit to use the Simpsons but I think he did it in a well played way. Using the duff vs Pawtucket beer case to poke at the years of claims that family guy is just a rip off of the Simpsons was great, having the characters in similarity sitting next to each other was a nice addition.
I could have done without the whole stewie/Nelson bit though. It was one of those things that needed to be longer to work out and because the bit was so short it was out of place.
Nice appearances by Cleaveland and Bob, a bit disappointed that there was no hank hill or Stan Smith involved, or even a teaser for future crossovers. All in all a solid show from Seth that did not shit all over the Simpsons legacy.