Heard the one about beer and nappies? It’s a piece of data warehousing folklore that alludes to the power of correlating data to uncover buying preferences and attitudes.

I’d like to believe that it’s smart to place beer next to baby products to lure men out shopping for the wife. But it’s rubbish, like much electronic information held about groups of consumers, employees and, for that matter, me.

My learned colleagues Daniel Taylor and Brian Partridge are getting all het up about who’s going to make pots of money out of rich subscriber data. They’re assuming of course that this data is accurate, manipulable and freely available to the diversity of companies vying to monetize it.

All of this I contend.

Living in Europe, where memories cast long shadows, I’ll stress that data privacy remains extremely pertinent to the political agenda. And whatever technical capabilities are on tap for global advertising mavens, it won’t be an easy ride to deploy them here.

In the past week alone, various European legal bodies have taken positions with important implications. Look at the European Commission’s recent draft directive on RFID privacy and security. Or consider the German Constitutional Court’s affirmation of a basic right of ‘informational self protection.’ Even European Union newcomer Romania has now asserted its position regarding data retention on fixed and mobile telephony and Internet services.

One of the joys of the EU - derived from its rule of subsidiarity - is that there is as much inconsistency in law as commonality. So boys, it’s ok to think big about the global advertising opportunity. But even if industry borders are arguably blurring, geographic boundaries still remain.