In Make It’s blog dump the other day, she linked to this blog which referenced Flickr’s guidelines about using linking commercially.
Flickr says (taken from their guidelines linked to above):
DON’T: Use Flickr for Commercial Purposes
Flickr is for personal use only. If you sell products, services or yourself through your photostream, we will terminate your account.
I haven’t used my flickr pictures commercially and I actually have to say I’m not sure I have seen others either. I’m sure some of the other crafty blogs that I visit do use Flickr – it’s cheap (or free) and easy to use – but I can’t recall any right now.
At any rate, be careful! You don’t want to get shut down.