Recent developments in Belgium may be of interest to anyone watching how the current UK regulatory reform is shaping up: the Belgium Gaming Commission (BGC) has recently implemented a blacklist of companies - including Betfair, William Hill and bwin.party - which all Belgian ISPs are now required to block access to.
Hopefully, given the UK's track record of fastidiously following European Regulation, they won't take this approach - since to do so would break EU / international trade regulations (for which they would join a short list of high profile countries that currently follow such an 'illegal' policy (US, France and Belgium)), not to mention imposing what is tantamount to censorship of the Internet on UK citizens.
Another country that recently attempted to implement similar measures is Israel. This lead to a landmark decision by the Court for Administrative Affairs in Tel Aviv which upheld complaints that the police in Israel had no right to order Israeli ISPs to block access to gambling sites.
Moreover - as this article points out - many of the big gambling sites are just blatantly ignoring these kind of 'blacklists', which suggests that the legislation in place really isn't worth the paper it's written on and would easily be overruled if it were to ever go to court.