I saw this in the bash_profile some setting: /perl5.10/bin

Hello Sergey. What you have there is just (part of) a path. It would help to understand immensely if you were to provide the full statement from the .bash_profile which includes that path.

my centOS 6.6 I find this: /usr/bin/perl. I am assuming this is where Perl executive are kept by default?

Yes. On CentOS 6 (and many other OSes) /usr/bin/perl is the default location for the system perl. You can try it by running it with that full path like this:

$ /usr/bin/perl -v

This is perl, v5.10.1 (*) built for x86_64-linux-thread-multi

Copyright 1987-2009, Larry Wall

Perl may be copied only under the terms of either the Artistic License
+ or the
GNU General Public License, which may be found in the Perl 5 source ki
+t.

Complete documentation for Perl, including FAQ lists, should be found 
+on
this system using "man perl" or "perldoc perl".  If you have access to
+ the
Internet, point your browser at http://www.perl.org/, the Perl Home Pa
+ge.
[download]

As to why the two profiles differ - you would need to ask the people who wrote them. Anything else on my part would be pure guesswork. Good luck.