I dont think 2011 will be cheaper, but it will be better. And ill bet you will be able to grab a 2011 board for $200-$300 when its releases. Makes more sense to spend $200 on a 2011 board than $200+ on one of these gigabyte 1155 board.
And mainstream doesnt mean budget but intel doesnt go after the budget market(sub $100 CPU's), they leave it to AMD. So as far as intel is concerned 1155 is their budget platform as its what they are offering the $120-140 low end i3 CPU's on. There is nothing enthusiast about SB with on die graphics. Enthusiast users will still have to wait for 2011, and use discreet graphics.