Spoon:
ive seen a lot of people manage with the automatic settings of the canon ixus or s line. would you guys choose this over canon powershot a line? havent started taking uw pics and when i decide to get my ist camera i want it right.
I'm not familiar with those particular cameras, but went through this sort of choice a couple years ago.
You should think about what your goals are, and what you intend to do with the photos. Your on land photo habits may also help you decide.
I rarely use my Nikon SLR on land, instead preferring to use a compact point and shoot for snapshots. My underwater photos are simply to 1) show my non-diving family and friends what I've been up to, 2) personal memories, 3) fish and critter ID, 4) to record that once-in-a-lifetime 18' purple-spotted-zebrafish that swims by on my solo dive
So far a small, simple, point and shoot with internal strobe has met my needs. Were I to choose again, the only thing I'd do different is to find one that has manual white balance and perhaps some fixed preset distance focus settings. (Others can tell you whether the cameras you are looking at have those features).
If on the other hand, you are trying for the very best quality, and dive photography is going to be the primary goal of your dives, then digital SLR with full manual controls and external strobes is where you should be headed.
There isn't any one answer that's right for everyone.