I noticed this yesterday with my mid-2011 21.5" iMac with 3rd generation Apple TVs running on a 4th generation Time Capsule/2nd generation AirPort Express Network. I click one of my Apple TVs, the TV screen turns black, audio comes through, but no video ever ends up arriving. I am unable to change the "Use AirPlay to Display" settings either; it's stuck on Extend Desktop.
Speaking of AirPlay though, ever since the latest Apple TV update that came out I believe in December, AirPlay has been very flaky with all of the iOS devices I've used, including the iPhone 5s and iPad Air. It seemed to still work with OS X though until 10.9.2, so now AirPlay is mostly useless across the board. Hopefully they push an Apple TV update out sooner rather than later as I'm guessing a lot of the problems might be there.
I generally try to keep things in perspective and not overreact when Apple slips up, but ever since the fall, I've had to deal with significantly more bugs than I have with Apple hardware/software in a long, long time. It seems to be one thing after another, and as soon as something gets fixed, something else gets broken. Too many updates that are supposed to enhance the experience degrade it instead. It hasn't all been bad, but given how prevalent some of these issues are, especially with Mavericks, it really suggests that they need to slow things down on the development cycle across the board and focus on cleaning up some of the messes they've made.
At this point, I really don't care about OS X 10.10 at all unless it was a sort of "Snow Mavericks" that was purely maintenance on what's already there. I'd be fine if a 10.10 that brought new features didn't hit for another 18-24 months if it meant that they'd clean up Mavericks and release a more polished 10.10. OS X has done nearly everything I really need it to do for awhile, except since Mavericks, there's too many things it doesn't do as well, and few things that it does better. And from what I've observed with friends and at work where I support numerous Macs throughout the company, I'm having a much better go of it with Mavericks than most people.
I put one Mac used at a retail location on Mavericks to test it out, running VMWare/Windows 7 for a few stray Windows apps still needed, and what once was a speedy, nearly seamless VM experience became a ridiculously sluggish mess that hogged tremendous amounts of memory, rendering multitasking all but useless. But even with the VM shut down, memory management is a disaster and bugs run amuck and I ended up getting several calls and messages everyday with problems and complaints, leading me to pull the plug on the trial run and put them back on the stable Mountain Lion. No complaints or calls since.
And given that I make money supporting computers, especially Macs, naturally my friends tend to call me when they have issues. Every other day I'm getting calls and messages about problems with Mavericks. Some of the problems are pretty extreme as far as Macs typically go, creating an experience that literally has become far less stable than your average Windows 7 experience. One of my friends has had their mid-2011 27" iMac crash/restart (I haven't seen the logs yet) several times since 10.9.2, one time to the point where even on restart, the system only half loaded and needed a hard restart to become functional again, and his Messages app freezes up the majority of times he attempts to use it, and this is just new 10.9.2 stuff. That is just sad, and it's hard to know how to respond lately when people scoff about how Apple products are supposed to be stable and just work. For awhile I was saying, "they're fixing it, 10.9.2 betas are working out quite a few of the kinks." All I know is that I'm definitely keeping my mouth shut about 10.9.3.
I know I wrote a lot off topic, but this is just striking the right nerve after close to six months of issues with iOS 7 and Mavericks and Apple TV. I want to believe that Apple will get it together and ultimately, I think they will, but it's clear that they've made some serious mistakes in the last year, though it almost all could simply boil down to trying to do too much, too fast, and without the proper resources to get it right. This is why it's quite worrisome to me that they might be adding the rumored iWatch and new and most likely expanded Apple TV into the mix this year, in addition to a new iPhone and anything else they have planned. They're doing a lousy job of supporting the products that they're shipping now; how are they going to support two more growing areas and address all the issues of the current products while maintaining the quality of experience and stability they've been known for? These broken updates are not instilling much faith in me, and that's not a position I'm familiar with being in when it comes to Apple.
Something's gotta give, sooner rather than later, or things do stand to start spinning out of control. I'm not at all suggesting that Apple's screwed even if things get a lot worse, because the competition is terrible more often than not. But I hate the idea of Apple getting to the point where we choose Apple products more because they're the lesser of two or three evils as opposed to choosing them because they simply offer an outstanding experience that sells itself. That is what Apple has historically stood for (especially once Jobs returned) and mostly delivered on. With Jobs now gone, it's all the more important that they get their acts together fast and get things back on track and avoid creating a destructive pattern with sloppy software releases.
The still-brilliant hardware absolutely deserves better.