I got my invite last week and integrated it over the weekend, but I need to hold off until I can accept USD.
According to John at Stripe "Unfortunately, right now you'd need a US-routable dollar account to accept payments in USD. We're planning on having better native support for charging USD in the future, but have no timeline on it right now."
I'm planning on opening a US bank account when I'm in SF in August, if anyone knows how I can do that from Ireland instead let me know.