Should I upgrade to Fedora 14?

YES!
i've not had a single problem upgrading to Fedora 14.
to be fair: not much has changed with F14.

Are there any features in 14 that you don't have in 13? Whenever I've upgraded for the sake of upgrading, I've been disappointed. There are no real improvements and I usually need to reconfigure things that I had fixed on the previous version.
I'd say to leave it alone unless you need something from 14.
I'm on Xubuntu 10.04 and I'm never leaving!

for the non-developing desktop users: no, sadly.
but the packages are more up to date.

also, if you use the dvd and select the "upgrade" option in isolinux, you won't have to reconfigure, it'll just upgrade all packages to their F14 versions.

but i get that you wouldn't want to mess up a working system. and besides, F13 will be supported (i.e. package updates) until one or two months after F15 comes out.

(i'm getting weird errors trying to submit this comment ~_~)

The commenting engine has been a little shaky lately, but it appears to be holding for the time being. I do appreciation the comment.

So if I'm understanding this right, I can use preupgrade, use the upgrade option from an install DVD (will a live CD work right? I'm using the Xfce spin), and I've heard that you can also upgrade via Yum.

If F14 allowed me to go back to the open-source ati driver, I'd do it right now. but as far as I can tell it's still a no-go for my graphics chip. And kmod-catalyst from RPM Fusion is in even worse shape in F14. In F13 it's woefully out of date; F14 doesn't even have it.

I am facing problems after upgrading to F14...
My laptop speakers stopped working.
Laptop is heating up. Also shutdown automatically few times.

F13 was much better. Although grub shows options for booting with F13, it is not working.