Sigma Offers "Price Drops" on Many Popular Lenses

Sigma is describing this most recent round of discounts as "price drops." However, they look like the typical-for-the-season instant rebates to me. Unfortunately, no Global Vision lenses were included in the price reductions.
 
There's no word on how long these discounts will last (I doubt they are permanent), so be sure to take advantage of the savings while you can.
 
Sigma Lenses with Price Reductions
 

Model	Rebate Amount
Sigma 8-16mm f/4.5-5.6 DC HSM Lens	$50.00
Sigma 10-20mm f/4-5.6 EX DC HSM Lens	$80.00
Sigma 12-24mm f/4.5-5.6 DG II HSM Lens	$75.00
Sigma 17-50mm f/2.8 EX DC OS HSM Lens	$150.00
Sigma 18-250mm f/3.5-6.3 DC Macro OS HSM	$200.00
Sigma 50-500mm f/4.5-6.3 DG OS HSM Lens	$150.00
Sigma 70-200mm f/2.8 EX DG OS HSM Lens	$200.00
Sigma 150-500mm f/5-6.3 DG OS HSM Lens	$200.00
Sigma 50mm f/1.4 EX DG HSM Lens	$100.00
Sigma 105mm f/2.8 EX DG OS HSM Macro Lens	$300.00
Sigma 2x EX DG Tele Converter	$50.00