I see a new Pinterest pinning menu on my account. I started to write a tutorial but decided to make a video instead. The new menu reminds me of the Pinterest mobile app menu, which is definitely superior to the desktop version. Below is a screenshot of the new menu and below that is the video.
The new desktop pinning menu work the same but displays your boards on the right-hand side of the pin image rather than underneath the image. The last three boards are shown at the top of the list, which is convenient when pinning in bulk to a particular category.