Since Flickr's announcement about its linking up with Getty Images it appears they may be looking to stop photographers who offer professional services from linking to their own personal sites.
Pablo Vincente, like many others, includes a link to his own web site - Digital Pixels - alongside the images he posts. However he recently received an email from Flickr asking him to remove the link and stating that "...Flickr accounts are for personal use and if selling products/yourself through your photostream [it] could cause account termination."
It seems that as part of the deal with Getty to set up a collection of royalty free, rights ready and rights managed photographs they may be uncomfortable about others doing anything that could potentially reduce their revenue stream.
That policy has always been in place - from discussions that took place in the groups a year or two ago, it seems that your profile is the place to put any links in to photo sales and photo pages should remain a commercial free zone.
The only difference now is that some of the images may be for sale through Getty which would beg the question, well if it's good enough for Flickr/Getty, it should be good enough for me.
Personally I'd like to see a field per photo so that I could provide a link for each photo and a 'buy' link would appear in a low key way (like the print button). It would be much tidier than people putting their own links in and heaven-forbid - banners.