A trip to London Zoo a few weeks back made me understand that a lot of people are investing in digital SLRs these days. I got one for Emily for her birthday last year, Although they take great shots in point and shoot mode you need to get to grips with manual mode if you want to get the best out of them.
I have collected together a few photography links from lifehacker that I found helpful:
The rules of photography composition
Master Your DSLR Part one
Master Your DSLR Part Two