Sales comparrisons of Casey's last two issues, with Austen's first two. Month, issue name and number, number of copies sold, and percent change from the previous issue. Keeping in mind these figures are based off the initial Diamond orders. I doubt reorders would affect this much, though. =)
Jul Uncanny X-Men #408 - 87,074 ( -1.6%)
Jul Uncanny X-Men #409 - 86,942 ( -0.2%)
Aug Uncanny X-Men #410 - 87,008 ( +0.1%)
Aug Uncanny X-Men #411 - 86,875 ( -0.2%)
Hopefully, things pick up.