While there is arguably strong foundation for a price increase, I wouldn't take a one week trend, viewing one data source, as indicative of anything. :shrug:
IMHO, it's only natural for eBay prices on converters to go up since there will be less of a supply of them to sell on there. No more dtv coupons = no more quick $10/$20 profit for people who ordered coupons with the intent to sell on eBay.