Because I am looking for information on opt-in and privacy laws in Sweden, I posted a question on LinkedIn Answers. L-Soft's Outi Tuomaala pointed me to one of their webpages that contains a table that gives a basic overview of email requirements in the United States and Europe. Of course you should always check national legislation in each country/state for more detailed information.
Tamara Gielen is an independent email and digital direct marketing
consultant with over 10 years of experience in online, email and direct marketing. 
The problem with the EU data you have given is that in the Union the European Commission issues Directives, which the member states must put into law. Each member state does this in a different way. What's more the directive only gives the minimum requirement - if a country already does more, that "more" stays in the country's legislation. (This of course is not the case with liberalisation policies, but in terms of minimum standards policies it is always true.)
In the UK it is perfetly legal to send sales messages by email to businesses, but NOT if you are trying to sell something personal. It is illegal to send a sales message to a consumer email address without prior permission.
Obviously UK consumers receive mountains of viagra adverts from outside the EU, but by and large there is nothing we can do about it.
Posted by: Tony Attwood | Jun 09, 2008 at 11:27 AM