Does one need to upgrade to 6.x-2.1

I started working on a site using Zen 6.x-2.0 and Zenophile to create / manage my sub-theme.
Now ./admin/reports/status tells me something is out of date which is just annoying.
What I'm wondering is do I need to / can I "upgrade" to Zen 6.x-2.1.
Is there a simple upgrade path or are there changes in 2.1 that will cause problems for my site created using 2.0?