I, frankly, loved Mort. I've found that, reading Pratchett's work, I don't find it "laugh out loud" funny, but it is consistently lighthearted, clever and humorous to a degree. There were a couple points in this book where I actually laughed, but the book had an overall feeling of whimsiness, of sarcastic, snarky humor with lasting appeal. As with the other (admittedly limited) Discworld books I've read, the world and characters are extremely creative, their personas, dialogue and feelings are extremely entertaining, realistic enough, fun.
I will say that Discworld is certainly not the pinnacle of literature. This is not a Guy Gavriel Kay or Pat Rothfuss, it's not an expose on prose, not a beautiful or lyrical piece of art. However, it's very well written, in a very intelligent and approachable manner. It's dry, it's snarky, and it's fun as hell. As with my review of The Colour of Magic, I'll say that this book makes me WANT to keep reading the series. There isn't anything in the book that I feel is a massive standout, but there's just something about this book that is heartwarming, that left me with a smile on my face, that made me want to recommend it to others. So I'll do just that - even if you haven't read Pratchett, or read any other Discworld, pick up a copy of Mort and give it a shot.