I have a couple of longstanding Gmail wishes.

1) The ability to select multiple conversations and collapse them into a single conversation. I would use this all the time... people who don't use Gmail don't realize the effect of changing the subject. It removes the utility of the "conversation" view and fragments the conversations.

2) The ability to copy attachments to other e-mails in your Gmail account to the e-mail you are currently composing. I tend to want to do this all the time, and I have to open another browser tab, search for the attachment, download it to my computer, and then reupload it to the other e-mail.

Other than that, I'm pretty happy :)

3) The ability to add a Google Stored Document directly from Google : When you attach a file you can only choose a file from your computer, it would be nice that Google list all your .doc, .xls or .ppt files from Google doc, your .jpg files from picasa and even your .flv movies from Youtube (why not!)

4) A real contact manager would be VERY nice (with tags for contacts, a list of real contact, and not a list of all contact you received a mail from)

5) A new interface ?