The two new tools they have added are Fetch as Googlebot and Malware Details. These are both currently under their Labs Banner.
This new feature will help you see if any malicious code is present on your site. It will highlight any pages which have malware code on it and help you find what is causing it by showing you parts of the page where it is present.
This will help you determine if your blog has been hacked. You can read more about this on Googles Online Security Blog.
Fetch as Googlebot
Another new feature is ‘Fetch as Googlebot’. This option lets you see exactly what Googles search engine spider sees when it visits a certain page on your website.
This is a little different from viewing the source of a page as you can see the HTTP header and server information as well as the regular code.
I encourage you all to drop by Webmaster Tools and check them out 🙂