I wrote a very short plugin to do just that. Turns out the plugin api for pyblosxom is quite easy to understand, and this hack was only about 10 lines.
pagetitle.py adds a new variable which will contain the standard page title, unless there is only one entry in view. If there is only one entry in view, the page title is augmented with the story title aswell. This makes search engine results and browsers happier, as they can recognize what your page is about by the title. User experience good, also good for search engines.
The new variable you want to use is: $blog_title_or_entry_title
If you want to get a better idea of what this plugin does, you can click the permalink below to view only this entry. The page title (in the url bar) should now reflect this entry's title.