Every "loyalist" who doesnt like 28 Days/Weeks Later films should think twice. I mean these movies revived the whole zombie/splatter/torture/gore movies genre. I really doubt Zombies would be that big today if this movie never would have been made.
The movies are pretty good. (the fanfilms as well)
I think they're terrifying because they are so much more realistic than the conventional zombie flick.
I mean, don't we often contemplate about the possibility of the military or some university scientist screwing up terribly with some virus and creating a pandemic?
I can't wait for the third part in the series, 28 Months Later, which will hopefully be as great as its predecessors.