Ah, my apologies for the assumption, it's been almost a year but I'm still too used to Reddit apparently!
Yes, the default launcher had ads, the SHIELD itself didn't, but I also didn't like any of the 3rd party launchers I used but I don't remember specifically why. Then, the SHIELD stopped booting so I didn't want to buy another one and went with the ATV instead.
As I mentioned, I wouldn't necessarily recommend it to someone who knows they'd regret not having the cast functionality, but, if you just want a device that works very well and doesn't ever have so much as a hiccup during navigation, it's been great!
I would still recommend the SHIELD for someone that wants cast or who wouldn't have a problem with (mostly) relevant ads being shown on the device (stock).
Yeah, and I can't speak for everyone here, but I didn't even bother trying it even though I was intrigued. It seemed like the kind of thing that could be completely game-changing and I wasn't willing to get hooked on another Googler's pet project that'd just get the axe in a few years. It's a self fulfilling prophecy at this point, nothing new is likely to get any traction because no one wants to run the risk and then Google cancels it. If they were willing to put in writing that they'll support something for x number of years (that's end user facing, not just whatever contracts they make with devs or whatever), it'd probably go a long way, but they're not willing to support an expensive flop if the product is what actually sucks, so, they're not likely to do that.
Hell, even anything older still runs the risk at any time :-\