So are they claiming it applies to servers owned by US companies or servers that are located in the US? For example as a European I'm hosted with Linode at their datacenter in London. Not that it really matters, apparently they are able to change the rules any time it suits them.
US Govt can force a US-based company to handover customer data from an overseas data center.
So no, you're not safe in London.
[In fact, due to close cooperation of intelligence services of the five Anglo-Saxon countries (Five Eyes), you're not safe in any of them if you want to do anything that challenges the interests that US law enforcement and intelligence protect. That includes any activity that would unsettle current intellectual property and copyright regimes, strong political activism, completely free speech, etc. If you're a web startup, that of course applies to your users too.]
Note to hastur: it looks like your snarky one-liners got your account auto-banned, so now nobody can read your comments that are actually interesting.
How much karma do I need to be able to read dead comments? Hellban is a pain, valuable comments keep getting lost every day. I don't think this keeps trolls away, this is definitely broken.
The UK is one of the few countries with a more active surveillance state than the USA. Hell, they have cameras everywhere there. (Don't teach 1984 in schools anymore?)
The US government generally considers anything on US soil, owned by anybody, to be their purview... but in the Megaupload case they siezed servers and data in new zealand, along with the USA.
Please, if you are British or live here, you know there are not cameras "everywhere". If you are not British and don't live here, please know that "they have cameras everywhere" is a lie.