The ticket is called the Orlando Flex Ticket. It can be found here:
http://tickets.visitorlando.com/Universal-Orlando-Orlando-Flex-Ticket/
It comes in two options: the 5-park (which doesn't include BG) and the 6-park (which includes Busch Gardens). In addition to the parks you listed in your OP, it also includes admission to Aquatica and Wet & Wild waterparks.
If you buy from
Undercover Tourist, the 2014 price is $356 per adult, tax included, and the ticket is good for 14 days.
A length-of-stay ticket for SW, BG and Aquatica is $149 per adult, plus tax, via the SW website (for a total of $159).
A 3 park unlimited ticket (Universal, IOA, W&W) is $190, taxes included, via
UT.
Those two options total $349, less than the price of the Flex ticket. But I think that the Flex ticket offers you the benefit that you only pay once per day for parking....so if you visit SW in the morning and IOA at night, you would only pay once for parking, save your receipt, and show it at the second venue (someone can correct me if I'm wrong on that).
Busch Gardens and SeaWorld both offer Quick Queue, and both Universal parks offer Express Pass, all of which can be purchased at the park on the day of your visit (pending availability).