Just got back from Boston, nice city. You can defs smell weed is legal there these days. Standard Q&A fare still applies at the airports too, and my usual advice to all UK travelers to the US still applies regardless of convictions: Do not waffle on with unnecessary details about your holiday plans to the immigration official. None of them care if you're really looking forward to going to disneyland or whatever. Just answer them as simply and quickly as possible, because you're holding everyone up.