Blink has to be among one of the best Doctor Who episodes ever! I just watched it recently on DVD and watched it again to catch all the subtle nuances I missed before like how old Billy knew when he would "exit" or rather how the doctor knew in order to tell him.
The intricate storyline invovling twists in time was brilliant! Despite the show being about a time traveler and time travel itself, very often very little is done with time. Usually the Doctor and co. arrive at some fixed point in some area and work things out from then and there going forward. It's nice to see time itself manipulated to solve a problem.
The resolution of the story was great for it's cleverness. It was ironic how the weeping angels in more ways than one engineered their own downfall by unknowingly allowing events to take place in the past that would influence the future/present. As for other shows' resolutions, I'll be honest that I have grown tired of the way sometimes the new Doctor Who solves difficult problems in seeminly a flash or deus ex machina. Fortunately all that was absent in this incredible episode. The Weeping Angels made for great scary monsters and the flickering lightbulb at the end....
I hope to see more episodes like this!