Test::Harness 3.00 is a complete rewrite, allows parallel testing

• Parallel testing. You can now say prove -j2 t/ and get parallel testing.
• Better timing support
• Ability to archive TAP from individual tests, making detective work easier, and allowing you to send results easily to an aggregator/reporter like Smolder.
• Better support for CPAN::Reporter
• Far more flexible API, with the removal of Straps.

Test::Harness 3.00 is a drop-in replacement for the 2.x series, unless you're using Straps. If so, you'll want the compatibility package of Test::Harness::Straps. If you don't even know what Straps are, then chances are you're not using them.

Test::Harness now has a new maintainer as well. Andy Armstrong has taken over the maintenance duties for the 3.x series, while Yours Truly will still maintain the 2.x series if serious bugs crop up.

(Be sure to read my interview with Andy Armstrong about the road to T::H 3.00.)