who lead perl5 develop?

Go to http://dev.perl.org/perl5/

5.12 won't be supported soon

I don't think you need to worry about that. 5.12 will continue to exist, and your programs written to 5.12 will continue to run just fine! How much "support" do you think you're getting for 5.12 now?

Does I need to upgrade my perl

Absolutely not. You may want to, in time, but you certainly don't have to. If your programs work great under 5.12, stay at 5.12.