Ask HN: Tips on going international

Hi all, one of the first pieces of feedback we've gotten for Alikewise.com is to expand beyond the US. The main reason we are US-only is that we don't know the legalities of going international, especially in relation to Terms of Use and Privacy. (Technologically, we can make it happen in a few days.) Anybody have any experiences with a US-based social site making itself available in other countries? For example, even if we operate in the US are we subject to EU privacy laws? If so, what are the issues to keep in mind? Our starting places would be Canada & UK. Thanks!