I'm curious as to why you expect the Black to suck. From what I've read, it performs fine with some slight lag occasionally. And I would actually gander a guess and say the Optimus UI is what's causing that occasional lag on the Black, and Virgin Mobile only allows stock Android. I see no reason why it should lag at all. But obviously it won't outperform the Triumph. The Triumph's Snapdragon processor is known more for performance while the OMAP processor the Black uses is more power efficient. Still though, with nothing but stock Android to push around, neither of these phones should lag.
Personally I think you should at least wait for the Triumph to come out and see what the verdict on it is before you go with the Optimus. If it turns out bad, you can fall back on your sit back and wait plan with the Optimus. If it does turn out to be a good phone, you'll be glad you waited for the extra power and features the Triumph brings. Of course, I suppose you COULD buy the Optimus and see how the Triumph turns out. If you end up wanting the Triumph you could always send the Optimus back since it would be well within that 30 day trial period.
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