Just found $199 each way from NY to London - even over spring break dates. http://www.britishairways.com/travel/fx/public/en_us?fromPkg=NYC&to=LON
$199 + plus $199 plus the fees and taxes? Still, probably in the $700 range, which counts as a good deal these days.
Well, the ticket I'm looking at was $199+$247 (for the date I wanted) and the total after tax was $647. So if you could grab one of the lower fares on each end it would run around $600. The taxes are crazy.