Almost every single time I type a question I end up having to go back and edit the title due to no latex preview. Obviously you can write the title in the body first to check it but it's very easy to forget to do that and it entails you then having to copy and paste it into the title bar. And that could hardly be considered good UX practise in 2015...having to preview something in a different textbox before copy-pasting into another one...
So why not have latex previewing on titles as well as bodies?