Question: Just like the newly presented iMessage but instead of just between iOS devices, with the Mac too.

I've looked at Handoff. It can only send links to the iPhone from the Mac.

I've looked at Droplr. It requires public sharing on a Twitter account. Not what I want.

I've been using email and have been recommended Evernote. But these solutions require a document that I must create, wait to sync, and/or later delete to free up clutter. I just want to send a quick message.

I just want an app/application pair that can quickly share links, notes, and pictures between devices, like iMessage.

Does what I desire exist?

Answer: 
Apple OSX Mountain Lion has been announced, it includes a few of the iOS apps on the mac desktop such as Notes, Game Center, reminders, twitter and message.

<http://www.apple.com/macosx/mountain-lion/>
iTunes.

iTunes will sync Safari bookmarks, Notes app notes and photos.

iMessage doesn't sync anything between devices. It's like GMail for text messaging. You access your text messaging conversations from any device.