Being impatient, as usual, I couldn't wait for the official release date, heh.
So far I've updated two of my Linux boxes (work and main home PC) using yum. There were a few hiccups, but nothing I couldn't handle. Mainly just some depsolving issues that required that I remove packages, and some signing problems that required I do "--nogpgcheck". I don't recommend doing it this way unless you have a pretty in depth understanding of the packages on your system, what they are for, and yum and RPM in general. If you care if you hoze your system, or don't feel confident that you can solve whatever problems come up, wait for the DVD release and upgrade that way.
After the updates were all done, /etc/sysconfig/redhat-release shows "Fedora release 11 (Leonidas)", and we're about a week out from the official release, so I figure not much will change before it officially goes to general release. Here's a gratuitous uname -a as well ;)
"Linux cube64.int.hozed.net 18.104.22.168-140.fc11.x86_64 #1 SMP Tue May 12 10:44:27 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux"
The only disappointment is that the on-board audio on my home system's motherboard still doesn't work properly under PulseAudio. Not a huge surprise, since it didn't work under 10. I usually use a USB headset, so it's not a show stopper, but it is a bit annoying. I really wish that the ALSA driver and Pulse would play nice. The sound will "work" if I disable glitch free, but it sounds like crap. I don't hold it against Fedora, because all distros that have switched over to Pulse seem to be having the same problems. I'm still amazed that the audio subsystem seems to be the most trouble prone part of Linux on the desktop. I can run DirectX games written for another operating system full screen at 1920x1200, do all sorts of advanced network magic, etc, but can't get sound to work right on a very common audio chipset (Intel HDA). It just seems so counter-intuitive. That said, when Pulse/ALSA play nice, it's awesome sauce. Hopefully by F12 this will all be straightened out, but I'm not holding my breath. I do think the various distros have jumped the gun a bit on making it THE audio subsystem, but I suppose it wouldn't really get widely tested otherwise.
On a good note, when using my USB headset, as well as the onboard chipset on my office PC, sound works flawlessly. Also, Pulse's CPU utilization has dropped to around 1% when playing sounds and under 1% when idle, which is an improvement. (doesn't hurt that I've got a quad core Phenom II at 3ghz though, heh, so YMMV)
But, anyway, this isn't meant to be an audio rant. ;)
Over all, things look more polished. I really like the changes to the update app. The audio preferences overhaul looks nice too, however power users may find it a little overly simplistic.
On a side note, I just upgraded to a 28" widescreen LCD, and everything looks sexier at 1920x1200!
Boot and shutdown times are noticeably faster. I was actually a little surprised the first time I rebooted. If it hadn't been for the delay when the Nvidia video driver's init script kicks off, and the time spent acquiring a DHCP lease from my ISP, my boot time from GRUB to GDM would have been under 20 seconds.
Over all, the system feels snappier, but that may just be my imagination.
Every piece of hardware was recognized perfectly from the first boot, and it "just works" with the exception of the audio stuff mentioned above. The only third party driver I have installed is the Nvidia driver, but that's for the sake of gaming, not general use. The video worked fine for normal desktop stuff on the open-source driver.
The virtual machine manager has a nice improvement in that you can assign USB or PCI devices to a virtual guest through the GUI now. I've been looking forward to that feature. There looks to be an easy GUI way to migrate hosts as well, though I don't have the setup to test that particular feature.
Over all, I'm very happy with my shiny new Fedora. I'm looking forward to the MythDora 11 release for my mythbox, and I'll be upgrading my other PC and my laptop, as well as our virtualization server at work to F11 soon as well.