That might be true if Apple was using 6G SATA drives, but actually they are using the SAME SSD's in the 2011's as they used in the 2010's. Heck my newly purchased 2011 MBA (i.e. yesterday) still has the 128GB Toshiba SSD that was used in the very first 2010 MBA.
So yes, a 2011 drive will work in the 2010 since THEY ARE THE SAME.