I’ve used both the BlackBerry and Android versions. I liked the offline compose functionality and the ability to upload images. Other than that, I found them slow and rather limited in functionality. Performance via the website is limited only by how fast your host is.
As for switching between blogs, that’s what browser bookmarks are for!
Lots of modern mobile browsers have the ability to upload from the filesystem – so I might look at integrating that with the WPMP.
Thanks for the comment.