Kevin Smith: Genius or fat bloke with a long coat? Well, he established his ability to make a good film on no budget with Clerks, that he could make a good arty film with Chasing Amy, that he could hit mainstream cinema with Dogma and that even he is capable of fucking things up royally with Mallrats. Jay and Silent Bob Strike Back falls somewhere between Dogma and Mallrats.
This film seems to have been written with the fans of his previous films in mind as much as a standalone vehical. In fact on ts own, I think it's merits would be harder to find. JASBSB is a parody of everything that Kevin Smith has worked on in the past with lots of (literal as well as figurative) nods and winks to the camera. This is also a weakness - how selfaware can a film be while still trying to be good?
I don't quiteknow what else to say - don't go and see the film unless you already know a reasonable amount about Kevin Smith. If you have enjoyed his previous works, well, then four cameos out of a possible five sums up how entertaining you will find it.