Thanks for sharing. Glad I'm not the only one. You can Save All attachments in Mail by selecting that command in the File menu of Mail. Didn't they used to have a button right there in the message for Download All?
Yes, I agree it is something that wasn't a problem before but is fairly recently.
I only have this issue with Mail.
If I use the Attach paperclip button and attach a JPEG and send that email to Gmail/Outlook/Yahoo!/Hotmail, the email arrives with the JPEG inline and there is no paperclip icon on the message like there is for emails with an attachment. Just tested again and in Gmail, the message from OS X Mail is not marked with a paperclip denoting attachment, but the image is inline.
If I attach the same JPEG in a new email message in Gmail/Outlook/Yahoo!/Hotmail and send it, it arrives as an attachment in all those apps, but it arrives inline in Mail.
My only solution is to use Outlook because my clients want their JPEGs and PNGs as attachments. They have complained.
In Outlook, I can do both. I can put a JPEG inline if I want by dragging and dropping the image into the email, or I can send an attachment by using the paperclip button and the images come as attachments. When images arrive as attachments, they are all listed in a bar at the top of the email message and not inline.