The OECD debate is ongoing, but many organisations must soon finalise their own internal discussions, as it will probably be too late to change when the tax rules are decided. Firms can continue to put processing where it makes sense to do so from an operational standpoint and pay whatever tax then arises. Or they can centralise all but the most basic proxy, firewall and load-sharing activities and so centralise tax in the countries where they operate real bases or subsidiaries. There will be merits and demerits in both situations in terms of cost and efficiency. The operative word is analysis.
Tax can make the difference between a healthy profit and a loss.
While it is depressing to have to design a Web processing architecture to fit the whims of tax collectors, prudent firms will not ignore the need to do so.