Yes, I've kept a very close eye on Premier League penalty statistics over the past decade or so...
Premier League Penalty Statistics 2002-03 to 2012-13
Nice. It does seem to show a trend towards more misses and saves.
From the numbers in the link:
Season ______ %scored ______ %missed _____ %saved ___ % fails
2002-03 _______ 85.94 _______ 3.13 _______ 10.94 _______ 14.06
2003-04 _______ 83.54 _______ 3.80 _______ 12.66 _______ 16.46
2004-05 _______ 83.78 _______ 2.70 _______ 13.51 _______ 16.22
2005-06 _______ 76.71 _______ 4.11 _______ 19.18 _______ 23.29
2006-07 _______ 80.00 _______ 2.86 _______ 17.14 _______ 20.00
2007-08 _______ 74.39 _______ 4.88 _______ 20.73 _______ 25.61
2008-09 _______ 80.72 _______ 9.64 _______ 9.64 _______ 19.28
2009-10 _______ 80.19 _______ 1.89 _______ 17.92 _______ 19.81
2010-11 _______ 78.22 _______ 7.92 _______ 13.86 _______ 21.78
2011-12 _______ 71.72 _______ 6.06 _______ 22.22 _______ 28.28
2012-13 _______ 66.67 _______ 33.33 _______ 0.00 _______ 33.33
TOTALS _______ 79.00 _______ 5.22 _______ 15.78 _______ 21.00
Keepers definitely do far more research on opposition penalty takers than previously....
The misses seem to be up as well. Compared to 2002-2005, the saves are up as you would expect from more goalkeeper preparation, but the misses are up more (nearly twice as many).