This is old, but randomly came across this TeX FAQ which explains why the version numbering of TeX is reaching pi:
Knuth has declared that he will do no further development of TeX; he will continue to fix any bugs that are reported to him (though bugs are rare). This decision was made soon after TeX version 3.0 was released; at each bug-fix release the version number acquires one more digit, so that it tends to the limit π (at the time of writing, Knuth’s latest release is version 3.1415926). Knuth wants TeX to be frozen at version π when he dies; thereafter, no further changes may be made to Knuth’s source. (A similar rule is applied to Metafont; its version number tends to the limit e, and currently stands at 2.718281.)
Reaching π isn’t as easy as it sounds though. So many iterations and still you won’t be there. You can’t achieve perfection.