Names that spring to mind for me are:
Highbank – Coonawarra; Dennis Vice's stunning red wine blew me away at a tasting of coonawarra reds a few years back, knocking the socks off established wines like Katnook and Terra Rossa from Parker.
Andrew Will – Washington; Chris Camarda's wines are nothing short of astounding, both in terms of their quality and of course their price (mitigated slightly by the scarcity of washington reds being exported.)
Craggy Range – New Zealand – The Sophia is developing really well as a Right Bank styled BB, with loads of potential aging left in the earlier vintages.
Sileni Estate – New Zealand – found a few bottles of EV Merlot/Cabs – one word – Stunning!
Havent tried that many blends from south america, its mostly been single varietals. The Supertuscans are getting a bit ridiculous pricewise – saw a bottle of Masseto on a broking list the other day for about £400. There are some good Cali blends – St Supery make a fantastic one, but you cant find it in the UK, so it means importing through someone and paying the premium, and with the pound against the dollar, that adds to the price. Id love to try some of the bordeaux varietals from New York though, but again cant find them in the UK.