Go Flickr go! I hope that this new investment allows them to add all the cool nifty features (especially printing and backup to DVD) that we have been asking for before the inevitable acquisition by a bigger company (even though I know and like Cal, Caterina, Stewart et al, I have no insider knowledge of what's happening, I just figure this will happen sooner rather than later).
Shameless promotion here: I'm about to become an investr in Flickr, so far as I can see the richest/deepest of the photo sites. After hearing about it for a while, I met with the co-founders, Stewart Butterfield and Caterina Fake, up in Vancouver where they live. (I had known them before, but hadn't really fooled around with the service, which in any case had been alpha then and is beta now.)
As many people are discovering, writing blogs is hard work - sometimes almost as hard as reading them! Photos are much quicker, and almost anyone can do a decent photo - at least of/for friends. and now that it's easy to post by mail, and everyone has a digital camera or camera phone, these services are becoming great ways to sell value-added storage.
My own experience is that it's quite addictive, and Flickr has a rich but natural-feeling set of social protocols. Each time you go to your home page you see a new set of photos (unless your friends are really slacking on the job and haven't produced any new photos). You can comment on your friends' photos and they on yours, send messages, set up groups for friends and group albums for events and so on, but there's less of the me-me-me feel you get on, say, Friendster, and more of the I-see feel you get from blogs (but without so many words, lucid or otherwise).