I have used both PB & Flickr and, for the purposes of on-line photo storage, I prefer PB.
After a couple of instances of my all rights reserved images being, er, lets say 'creatively borrowed' on flickr and a couple of commercial travel & tourist companies wanting to somehow 'be my friend' on flickr (presumably based on my tags) I decided to retreat from Flickr. I also don't like the ubiquitous use of the Flickr API utility which just seems to lend itself to you, the photographer, not being in full control of what you post up there.
Now I suppose many Flickr users in TP-land will come back on this post and provide lots of info on how you can control this but I just felt very uncomfortable with Flickr so chose to take my images off.
On the other hand, to it's credit, it is a fantastic source of images & groups on all subjects you could ever imagine and for sharing with others it is very slick indeedy
Just my $0.02
BTW, best regards to Edinburgh .... a Dunfermline expat myself
Dave B.