It looks good. The feature I'm constantly missing though is 'Mark as read' - it would be a nice addition to 'Move' and 'Delete'.

EDIT: Actually it appears to set it as 'read' by clicking on that little envelope - is that right? I always try to open the message by clicking it but ends up double-clicking the title instead. In any case I still would like to see the 'mark as read' option along with the 'move' and 'delete' options in the menu.. they're related. In fact what I wish for is a more gmail-like approach.. where you can tick selected messages and apply an operation on them (e.g. mark-as-read, delete etc.). I'm getting so used to the gmail interface by now..