There's been numerous ideas thrown around for GNOME Three Point Zero (ToPaZ) in the community - the Wiki, mailing lists, conferences, planet, etc. I took a bunch of them and created a mockup or "storyboard" of what I imagine 3.0 could look like.
The tagline is "A First Class Desktop". There are two key ideas:
Tags can also be used to build up "aggregates". Tag all the people (i.e. contact details) on my football team and I've got a mailing list. Tag a bunch of songs and I've got a playlist.
And, I know that real topazes aren't blue, but blue is what I got from OpenClipArt. This is a mockup of vaporware - the "screenshots" below won't be pixel perfect, and the icons are a total mash, but I hope that the ideas come across. Anyway, on to the meat...
Taking the first of Fitt's corners is the Open Menu - opening things is the most common task that I do. Either opening "the web", or opening "my stuff".
Opening a "Web Page" gives you something a lot like current Epiphany - the location bar also doubles as a Google/Yahoo/A9 search box and does EntryCompletion from your bookmarks' titles.
Other Open menu options basically bring up Beagle/BEST. "All Documents" gives you everything, but you can refine by type (e.g., the Address Book is conceptually similar to searching for all "documents" or "things" of type "AddressBookEntry/Contact/Person") or refine by tag (e.g., Important, Bookmark, Trash) or refine by date (e.g., "this week" will give you appointments, mails, as well as browser history). Documents that you have not given a title (or subject, for mail) are automatically tagged "Drafts". Documents that you have not read are "New", otherwise known as your Inbox. Note that "New" things have a yellow star icon.
The Create Menu is how you make new stuff. It's like the current Applications menu, but flatter, and without the applications. Installing Inkscape-like software would add an "Illustration" entry to this menu.
The Manage Menu houses your preferences, as well as system tools like the Terminal.
We'll come to the panel launchers in the middle a little later. On the right...
There is an Eclipse-like common space for "long-running background activities" to live. These are things like downloads, mail/pda sync, printing, virus scanning, software updates. Following the menu entries gives more options for individual tasks.
Clicking on the clock opens the calendar for today, and in Fitt's second corner is something a lot like the current Window Selector applet (although when you click on it, the menu that pops up also incorporates the Workspace Switcher). Super-Left and Super-Right cycles between workspaces (Super is the "Windows" key between Control and Alt), kind of like metacity's control-alt-left and control-alt-right. Super-Up and Super-Down cycle between open windows, kind of like Alt-Tab, but it doesn't re-order the list the way Alt-Tab does.
In the middle are panel shortcuts - to "documents", which could mean people (Address Book Entries), spreadsheets, mail conversations, beagle searches, photos, etc. etc. Here I've clicked on the shortcut to the "Jeff Waugh" person, which gives me a central place to communicate with Jeff - mail, IM, blog.
We now have an open document, so we have a top menu bar - it's MacOS style menus. They're controversial, I won't go into the arguments for and against them here, but they're in the mockup. Back and Forward buttons so that if you open a search that found an e-mail message that had an attachment which was a spreadsheet... when you get to the spreadsheet you can trace your steps backward. The interface is consistent with respect to hyperlinks - left click to follow, middle click (or Control click) to follow in a new tab, regardless of what "application" should handle it. Filling out Fitt's last corner in the top right is the close button.
Just left of the close button is the document title (or person's name, or e-mail's subject), which is a menu for the tags on this document. Add the "panel" tag, and they appear in the middle of the bottom panel, like current panel launchers. These shortcuts are also decorated with emblems like "New", so that if I have tagged my "Jeff Waugh" AddressBookEntry with "panel", then his icon gets a yellow star when I have new (i.e., unread) things associated with Jeff. New mail, new chat, new blog posts, his calendar changes, etc.
Similarly, the "desktop" tag puts a shortcut to the tagged item on the desktop. The first four tags are "built-in", and can be quickly toggled with keyboard shortcuts. For example Super-Shift-1 flips the "Important" (!) tag. Super-1 opens a new Beagle/BEST search for everything that's tagged "Important". "Important" is like "starred" mail in GMail - it means whatever you want it to mean.
In this example, the "gnome" tag has been assigned to Super-(Shift)-5. The other tags do not get menu entries, but can be found under "Edit Tags...". Inspiration comes from Epiphany's bookmark topic mechanism.
I followed the "439 messages" link (results are in the same window), and then refined my search for the term "topaz". For the heck of it I also created a mail message and opened a spreadsheet - they don't have focus, though, so they're dimmed.
Do imagine some window borders - I couldn't figure out how to GIMP them in without fiddly effort. And whilst we're imagining things, let's add some drop shadows, and wobbly windows... :)
There are, however, no title bars. The actual title lives in the top right hand corner. And to move windows around, just right-mouse-button drag, kind of like the way metacity handles alt-drag to move windows around. Also, middle mouse drag pans a scrolled area, just like inkscape currently does.