I liked it.
Susan only appeared to have one facial expression, which bothered me a bit. The first Auditor's voice startled me. I didn't imagine it anything like that.
The eater of socks was extremely cute. Ridcully was good too. I got used to Death's voice very quickly; like others I expected it to be more BOOMING, but it still worked for me.
Albert didn't seem old enough.
I liked Nobby and Visit, although Nobby seemed very smug.
Perfect casting for the Oh God
I loved the beginning sequence of the Discworld in space, so I was pleased they showed it twice. The synopsis of the first episode at the start of the second did take a very long time, and the preview of epidsode two pretty much told you everything you needed to know rather than offering teasers. But that's nothing to complain about really.
I adored Banjo, and like Wendy, loved the bit at the end when he got the puppy. Nigel Planer was excellent as Sidney. Hex was well done as well.
The voice of Teatime was a bit annoying at first, but I got used to it. By the end it didn't seem as if any other voice would suit him at all. He certainly looked the part.
I didn't think they cut out anything too important, but I do agree that anyone who hadn't read the book may have been a bit lost at times. A peril that faces all book to film translations.
All in all I thought it was pretty good.