As I've pointed out in the update above, I reran and maintained ordering. I thought perhaps it was an 5.8/10 issue, but ran on my Linux box and got the following:

               Rate while_shift   OP regex ike2 double_split chromatic
+ jwkrahn ike1
while_shift  15.0/s          -- -11%  -30% -40%         -46%      -51%
+    -54% -54%
OP           16.8/s         12%   --  -22% -33%         -40%      -45%
+    -48% -48%
regex        21.5/s         43%  28%    -- -14%         -23%      -29%
+    -34% -34%
ike2         25.0/s         67%  49%   16%   --         -10%      -18%
+    -23% -23%
double_split 27.9/s         86%  66%   30%  11%           --       -8%
+    -14% -14%
chromatic    30.4/s        102%  81%   41%  22%           9%        --
+     -6%  -6%
jwkrahn      32.4/s        116%  93%   50%  29%          16%        6%
+      --  -0%
ike1         32.5/s        116%  93%   51%  30%          17%        7%
+      0%   --
This is perl, v5.8.8 built for x86_64-linux-gnu-thread-multi
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Anyone have an idea why my regex engine is so fast for ActiveState Perl 5.8.9?