In addition to the 24mm f/1.4 Art lens, today Sigma also announced the price of their 150-600mm f/5-6.3 DG OS HSM lens (Contemporary version): $1,089.00. Adorama and B&H are currently taking pre-orders. Shipping should start on March 20th, 2015.
The Contemporary model of this lens is lighter, cheaper and with a slightly simplified lens design compared to the Sport model that is almost twice as expensive: