We have a new release of the blog module available: 0.2.1
Download here: http://www.silverstripe.org/assets/modules/stable/blog-v0.2.1.tar.gz
Post bug reports here: http://open.silverstripe.org
This release fixes an issue that came to the attention of the SilverStripe development team in the last couple of days. They could potentially let malicious users bypass the CMS security. For this reason, we strongly recommend that you upgrade all of your sites that use the blog module.
The security fix is the only difference between 0.2.0 and 0.2.1, so the upgrade should be straightforward.