I can see how it would dissapoint on some levels, since 'Talisman' was a sweeping epic and 'Black House' is all set in one local, but that's about as dissapointed as I got.
'Black House' was amazing, probably one of the best things King has done since 'Bag of Bones'. The tie-in with the Dark Tower series sent chills up and down the ole' spine, cause I'm dying to get back into that world, but the overall story itself was good enough that you didn't really need to read 'The Talisman' or any DT books to enjoy it.
Seeing Jack all grown up was great, but I found it odd that they never specifically stated what happened to his mother...