GOOD 
Visuals. Some of the best I've ever seen in a computer game. The characters all looked superb.
Music. Absolutely perfect, captures the mood and style of W&G.
Characters. Apart from Mr. Gabberly, I enjoyed meeting every single character, moreover I wanted to know what they had to say. Many characters in adventure games can bore you to tears, but not this lot!
Locations. Looks like an old town in Lancashire to me. Spot on.
Episodes. Each episode was entertaining to play, but "The Last Resort" was particularly outstanding.
BAD 
Wallace. Although Ben Whitehead sounds a lot like Peter Sallis, at times he sounded a bit stressed out, even when Wallace wasn't.
Gromit. He didn't seem to be as emotive as he is in the films. It was hard to see what he was thinking at times, unlike in the films.
Mitsakes 
. A few Americanisms ("quilting bee", "kidney pie") crept in, along with the odd Amglish spelling oversight.
Tea bags with string? What do you think a tea pot is for!
Aardman should have sent someone to work with Telltale to spot these things, so
I blame them for the bad bits.
Overall, as a Wallace and Gromit fan, I have to say I enjoyed these adventures immensely, and can only hope that a second series will follow.
Well done Telltale!