Well, it would seem most of virgins phones are spin offs from Sprints line of phones.
I would imagine that they are going to ride the Optimus V wave for awhile (i have one too, its awesome)
and in a few months or so when the next generation of high end dual core devices are on major carriers, the other carriers will pick up last years high end devices.
I can almost forsure see Virgin Mobile getting either the Samsung Epic (which is a galaxy S with a slider keyboard) or a really unique phone thats not on sprint.
Most likely it will be the epic. the Galaxy S 2 is rolling out soon and they will want to keep producing last generation high end phones to keep revenue coming in since manufacturing them will be cheap. (the product is already mature and costs are lower to make it then when it was new) also the epic is already compatible with sprints cdma network. its a shoe in for the next virgin mobile device.
Although if reality takes a strange left turn I can also see Virgin adding a slightly higher mid range device to their line up. I strongly strongly hope they put quality before all else...
They made a good choice using LGs Optimus series, its a solid performing phone, sells well, great middle ground between cost and performance. they also made a BAD choice with the intercept. I guess virgin just really wanted to say they offered an android phone, and Samsung pitched the intercept and since it was available in the price range virgin sells phones at, everything just kind of worked.
This is getting kind of long winded, I guess the jist of my speculation is that I believe when the next generation of dual core smartphones becomes as mainstream as 1GHz "high end" phones are today, then the older high end will become the mid range, and we ALL benefit from that.