If you use WordPress 2.00 then please be aware of the following problem with new WordPress and Post2Blog that caused by error in WordPress: 

WordPress extended text entry tag not working in posts if you add new post using external application such as Post2Blog. This is can be fixed

Bytescout Software Blog » Blog Archive » WordPress 2.00 bug-fix

Here is another annoying bug in WordPress 2.00: image/files uploading via blog engine is not handled correctly anymore (comparing to WordPress 1.5.x)
Bytescout Software Blog » Blog Archive » WordPress 2.00 image uploading bug