Posterous aprouch to blogging is great!, yes if you post from your email, you may be able to post from any place, any time.
But when you post pictures, with text, you do not always want to have the picture on the top, and text in the button. If you use gmail, you can now insert images in the middle of the text. First go to settings in you account then go to labs and from the list enable "Inserting images" app, after that you will have this when writting you email. Now all you need is to click on image icon, choose from an image on your disk, or from an Internet url, and you are done.
Thanks buddy, this is helpful.
You are welcome.:)