Thanks David for yet another interesting post on BB and the law. Compared to these legal tangles, sorting out a slow connection is easy 
If anyone is interested, there was some stinging judicial criticism of the practice of sending letters demanding several hundred pounds to alleged copyright infringers (known as "speculative invoicing") in
Golden Eye (International) Ltd & Anor v Telefonica UK Ltd [2012] EWHC 723 (Ch). In that case, the judge granted the
Norwich Pharmacal order sought by Golden Eye in relation to content where they had an exclusive licence, but rejected the
Norwich Pharmacal orders sought by Golden Eye on behalf of other rights holders who had engaged Golden Eye to enforce their copyrights in return for a proportion of any money received.
I haven't been following the case law in this area, so I'm not up to date with the latest developments. What
Golden Eye shows is that not every request for a
Norwich Pharmacal order in relation to online copyright infringement succeeds, but any failures are likely to relate to the way the data is likely to be used, rather than due to any action by the ISP. Indeed, in
Golden Eye, O2 had agreed to disclose if a court order was made and were not represented in the proceedings. The proceedings resulting in the judgment I linked to were primarily between the claimants and Consumer Focus, intervening on behalf of the (at that point unknown and unaware) defendants in any actions resulting from the
Norwich Pharmacal disclosure of data.