A thousand people per realm dumping badges into gems and saronite means you can't sell your gems and saronite even for the price of FREE once Cata hits...
I've got ~630 badges. I've already bought almost everything except the 1-handed tank heirloom mace. I might buy that one too, I'm not sure. Regardless, I'm just going to let ALL my excess badges convert to golds. It's easiest that way.
I'm planning on having a load of gems on the AH on the night before the patch going live. A lot of stats are changing in 4.0.1 (AP -> Agi, ArP->crit), and at least combat rogues and hunters will "need" to regem, so there should be a lot of demand around.
You'll have to convert them to something other than triumph then, as your first 1400 frosts and triumphs will all become justice points. On my realm, primordial saronites are going for 400G each still, which is 17G per frost, much better than the 5.5G per valor/heroism the converter will do.