I started using Flickr in November and almost immediately upgraded to the "pro" account. So far, no complaints, though it has been slow uploading as described here, but I've written much of that off to being in Sydney.

One solution to their problems is to gate bandwidth upload on a rolling period (28 days?) instead of on a calendar month period. Would even out the spikes they apparently get at the start of a new month.

Ooh, and I just thought of another thing, on Windows at least they should try piggy backing on the BITS service which I've been playing with for Azaleos. Would slow down uploads a tad but even them out and allow it to occur in the background.