[petrochemist]

Hi Peter
I'm another user of Flickr. Although I've put about 100 pictures up and probably originally joined to share photos that were taken on my compact cameras (not suitable for the brand specific forum I used exclusively before joining), that's a minor part of the use of Flickr to me. As Al mentions it's the groups that make it work for me. Whilst many of the groups are little more than ways of getting people to view your pictures, there are others that have active discussions, many in fields that are highly specialized. These can be a simple way of getting tips on the more obscure aspects of photography, or supporting software. I've found some of the infra-red / macro / panorama / DIY groups very helpful.
In addition I sometimes come across groups that suggest a new technique to play with (such as using UV excited fluorescence - which I came across looking for information on photographing using UV wavelengths only).
IIRC it was via one of the discussions on Flickr that I was recommended to try WPF. (Thanks Don!)