"The Snows of Summer" is a really nice adventure. On the pro-side, it has a pretty nice "frosty" feeling and sets the tone for the adventure part. It also delivers a strong hook for future installments that is even able to keep a group of evil PCs together. Most encounters are fun to play.
I was a bit disappointed with...
...the linear design. The adventure railroads the PCs from encounter to encounter - not much room to develop individual plans (except for the two dungeons perhaps).
...the difficulty: Especially if the characters are able to provide a reliable source of fire-damage, the adventure turns into a cake-walk. On top of that, the adventure offers a huge lot of treasure, which is a bit too much for my taste.
Overall, it still provides about fifteen hours of entertaining, if a bit bland, fantasy-action.