Hi,
Upgraded from 1.6.8 to 1.7.0 and I have noticed two changed behaviours:
1) Email notifications of new comments arrive with the titles undescored: You_have_received_a_comment
2) When you are posting and you highlight a word to use one of the buttons, like bold or italics, it says “In order to use one of these buttons you must place your cursor in a field”. This happens in the text area field on all tested blogs since the upgrade.