First of it was fantastic to meet up with old friends again. We had a good chat and went for a pre-show meal together with excitement building by this point, even for me (having already seen one of the previews).
Onto the show and apart from the missing song discussed elsewhere, which I honestly wouldn't have noticed, it was barely any different. The band was revealed early into the show briefly as well as at the end which was new (previews it was only at the end). The only other differences I could detect were tiny alterations to the script, not the plot but just the wording in some places and the addition of a few more jokes I think. Maybe it was just the fact I had already seen it but the show appeared to go by quicker. I didn't time it so maybe it was just my imagination. Funny that the missing song I didn't notice yet I did notice tiny script alterations! I suppose that says a lot about how wonderful this show is, even without the great music from Mr K.
Another difference from the previews is that they now have a selected amount of merchandise:
Tote bag
Poster
Programme (improved)
The improved programme has increased in price (as Jbaent already said) from £3.50 to £6.00 but now has an interview with Mark and some nice pictures from one of the preview performances. Also, they have updated the list of songs! It's altogether a better programme and superior to a tour programme.
Anyway, lovely day with lovely people. Roll on May!