When using mobile, the horizontal home screen is nicely laid out, with most major features of the full page visible. But when you flip to vertical, you lose a lot of the info: timestamps, latest thread, etc. Within individual threads, the horizontal layout is also pretty good. But when you swap to vertical, user info is compressed and missing. There's a waste of empty space to the right of the username. Edit: Also, some more issues: Sigs disappear in vertical, which is fine, but you may want to throw a border or a few line breaks between the end of a post and the edit, reply, quote buttons. It feels a little text wall-ish. The floating mobile quick post editor is a little too large. It fills the whole screen and makes touch manuevering a hassle when you're trying to move the cursor to the edge of the screen. Not a huge problem though as you can always click more options and go into advanced posting.