The GUI is extremely simplified thus it's pretty easy to learn to use it (especially if you're coming from the Mac OSX environment :D) but as mentioned, most of the time we'll have to depend on "external" applications when it comes to "computing" or doing certain things, since Gnome does lack some features.
Anyhow, I don't know if we can call this feature a "must have" but nonetheless, if you want to make Gnome automatically change its wallpaper, well, by default you can't.
Although it has a simple desktop customisation window which lets you do things like change the wallpaper, add pictures from online sources (Gnome artwork, etc), change font, etc but it won't let you automatically change the wallpaper on a timely basis.
In that case, especially if you use Ubuntu Linux (the app maybe available for other major distributions) then there is an excellent utility called Cortina that does exactly that!.
*. Once installed it'll run from the notification area and let you add wallpaper locations from local storage devices such as HDD/USB, etc easily.
*. Change the wallpaper from a timely basis automatically, finally! :D.
*. Lets you choose it to run when the desktop is loading.
|One thing though, once done configuring, don't click on the "close" button at the title-bar, use the big "Close" button below instead, otherwise it'll exit from running thus no more automatic wallpaper changing, etc...|
*. Set pictures to - Zoom/scale/centre/spanned, etc
*. Change the time-frame.
That's about it. It's an amazingly simple yet extremely useful app if you want to automatically change those wallpapers nonetheless.
You can install Cortina in Ubuntu 11.04, 10.10 or 10.04 by using its PPA. To do that, open your GNU/Linux terminal and enter the below command.
sudo apt-add-repository ppa:cs-sniffer/cortinaThat's it. Once installed you can access it via: "Applications" -> "Graphics" -> "Cortina" in classic Gnome desktop. Enjoy it!.
sudo apt-get update
sudo apt-get install cortina