I have just upgraded both my laptop and desktop machines to Fedora 19. Having had a few issues with the past couple of releases this upgrade has been almost flawless. The only issue I have noticed so far is some missing fonts/images for the grub 2 bootloader but everything works otherwise.
The biggest improvement from my point of view is in graphics performance. I have an ATI card running the opensource radeon driver. I had noticed stuttering during video playback on Fedora 17 & 18. This release however it has vanished and smooth video has returned. So far so good.
/boot/grub2/themes/system/DejeVuSans-10.pf2 not found
/boot/grub2/themes/system/DejeVuSans-12.pf2 not found
/boot/grub2/themes/system/DejeVuSans-Bold-14pf2 not found
/boot/grub2/themes/system/theme.txt not found
The boot message about grub not finding the fonts or theme is due to the starfield theme nolonger being the default. Install grub2-starfield-theme and then it works as before. The default for new installs appears to be a plain console theme.