I have not been back in the game long enough to know if any of the ID companies, most specifically HSU ever offer any special deals around the holidays. Have my eye on an HSU VTF-15 but have time to wait.
I did some digging and shadyj appears to be right.
Lots of Subs were on sale last year, Klipsch, BIC, Polk, but they were all 10-12" models and not close in range to the VTF15h. HSU had the VTF-3MK4 on sale for $50 off, Epik had the Legend for $100 off and Rythmik had the FV12 $50 off 2 years ago. I know I've seen Outlaw have theirs on sale as well. However I have not come across anything at the VTF15h's level going on sale.
That being said, I'm in no rush either and BF is less than a month away so might as well wait and see.
Also they are not 'volume' manufacturers. Sales are usually run to lower excess stock or promote brand awareness. ID companies have a hard time keeping stock up without sales. i suppose I'm hoping that some companies bite on the second thing. You'd be surprised how many deal sites and specific Black Friday sites are out there and as sales pop up, large forum discussions talking about the quality of the ID product vs the mainstream brands can create positive buzz.