Some interesting and useful techniques listed in this thread. Like shriekingviolet I always do the "five people are" clues first. I consider it one of the more important clues because it helps to eliminate choices right away and can be dealt with much more quickly with a clear board.
I like JulieC's point also about being careful of the interval. Most of the jumps are of one or two units, but there's a group of puzzles where the interval is three and I can't tell you how many times that's messed me up when I'm not paying attention.
And to Anthony33, when I first started solving on this site my average time was about 30 minutes if I remember correctly.
It really does improve once you've gotten more experience.