Pros:

+ Very good map layout and design.
+ Length of maps was fine. 
+ Plenty of challenging moments, lots of zombies.
+ Good weapon variety, well placed weapons and ammo for the most part.
+ Interesting finale with the colours changing and the Alien place. Reminds me of something out of Crysis. 

Cons:

- There is a problem with the Bots using the ladder in the final map, having played through the campaign twice, the same thing happened, they would fall down, or get stuck at the top and another bot would climb back up, then fall down, this wasted medi's for the finale. 
- Lack of Ammo at the finale, if there is some ammo, I don't know where it was. 

Conclusion:

Overall very good, one of the few good futuristic/alien related campaigns I have played. It's fun, challenging, and is about the right length for a campaign (took about 1 hour 10 min on Normal). Everything was well laid out, easy to follow directions and fun to play. The only draw back for me being minor glitches with the bots on the ladder in the final map, which was quite annoying in an otherwise glitch free campaign. 

Pros:

+ Very close likeness to the original Goldeneye, lots of nostalgia.
+ Some great scripted events.
+ Great dialogue between survivors, some very funny.
+ Easy to follow directions and layout, never got lost on first run.
+ First two maps are great, well decorated, very dark and immersing.
+ Secret rooms were good.
+ Interactions were good and varied.
+ As a stand-alone finale, it was good, challenging, varied and included a space rocket.

Cons:

- The final map has no resemblance to the other two in terms of location, weather, conditions, I realise it's a recreation of several separate areas of Goldeneye 64, but this disturbed immersion somewhat.
- For me personally, over the first map, the silenced SMG (P90 for me) was too frequent, a better variety early on would have been nice.

Conclusion:

One of the better campaigns I have had the pleasure of playing, the first two maps are very nostalgic, the dialogue is fresh and funny, minor drawbacks don't take away from the overall positive ones.