I think Rio must be dumping this stock as the number of Ebay listing of these items has rocketed 100 fold since 1 month ago.

in mid to late December there were about 2 or 3 on sale in Ebay, now there must be dozens for sale.
One guy is dumping them at 99.95 - which is the Tiger Direct price, but he charges $USD15 shipping - which may be more than TD charge for the same item.

All Ebay items are listed as 'brand new factory sealed' units, which would imply they come from the same warehouse as TD's stock does.

Either this product is going the way of the RioCar [i.e. EOL'ed] or its making way for a newer model.
To be honest I expected the Empeg guys to have been working on a sucessor to the Mk1 RioReceiver by now, and the fact that they are planning on tweaking the software after the RioCar release 2.0 software is out is another indication a newer model is on the way I think.
But I have no idea how long it will be before its released and/or what the price will be - certainly not $USD99 each for a while!