That is a notorious blog program issue and one of the biggest reasons I stay away from Blogger in partiular - but I've not used wordpress a ton so haven't had the problem where it ruins the entire post at 'save'.
Was there *any* of your post that was copied and pasted? If so, remember to alway use the 'deformat' option on those bits and pieces before publishing - often times when you copy and paste from another site the text carries the formatting from that site's design elements with it - effectively ruining any fomatting you've done in your blog post.

If you didn't copy and paste anything in, I honestly don't have any ideas other than to say WP isn't exactly the most fabulous example of clean or stable code

It's frustrating I know...

__________________