Diythemes has released another version of one of the dashing theme (Thesis Theme) for wordpress bloggers. The new released version Thesis 1.8.1 will fix the squashes bugs and saves cache pages to ensure fast loading of your blog in all modern web browsers.
Chect out the features inside Thesis 1.8:- Thesis 1.8 Rocking
The purpose of removing cache busting query strings at the end of page <head> section is to ensure that users get updated cache version of the visited page.
If you were previously making changes to your thesis theme design and the changes were not coming instantly, by now the changes will come immediately.
Although this is a minor update but still it will effect a lot on the performance of your blog in term of fast loading and offering updated cache pages to visitors.