I really don't get this "well Vega failed, AMD should just completely write it off and not even release it" nonsense. It is so outright stupid that I can't fathom why there's so many people that keep stating it. We've consistently seen that mining means they can probably sell every card they can make even if its not price competitive to Nvidia in games. Heck even if things work in the opposite, where say some new mining development that Nvidia excels at but AMD somehow sucks at, so all the Nvidia cards get bought up and Nvidia's already premium pricing going to new levels, leaving AMD cards the only means for people buying new. It seems very possible that the changes will be like GCN in general, where AMD relies on their sustained software improvement to bring out their full performance (so, no there almost certainly won't be 40% improvement at release or even by the end of the year, but give it time, say 1-2 years, and I bet we could see a consistent 20-33% improvement, with it possibly pushing higher under ideal conditions such as DX12 games that utilize certain features well; I have a hunch that we'll start to see more of the tricks used on console games be utilized in the PC space, and One X 4K could benefit Vega especially well on some titles, and it will take a while before developers wring out what improvements the One X will enable). That won't happen if there aren't cards to work with.
Not to mention, not releasing, especially after they've already done PR for it, would be a disaster, bigger than releasing a subpar card (and it very well could just be that their initial implementation of Vega as a chip is a dud, and that it requires serious tweaking, more than just a respin, to bring out its potential - much like we saw with the evolution from the 2000 to 4000 series; with Navi possibly being a way they realize the gain made from the 4000 to 5000 series, doubling the GPU effectively as well as offering similar gains that we saw Crossfire make around the time by using more). Since they almost certainly wouldn't shelve Vega and publicly state that it is a failure (since then people would say that proves that AMD's architecture itself is a failure, killing its future potential including use in APUs and setting off a firestorm of BS; not to mention it would also effectively give the people that have been claiming that GCN is a total failure for years now, unwarranted validation; plus it could even hurt console sales). People are already calling for AMD to just kill their graphics business, imagine what would happen if they were to scrap a major release entirely. People seem to actively want them to go out of business for some bizarre reason.
This place gets more and more ridiculous. Prior to every single AMD release, this place gets worked up into a frenzy over rampant speculation (both ways, positively and negatively) and hyperbole. Then the release happens and it pretty much goes as expected (which is to say, about splits the rampant speculation; typically offering decent but not spectacular performance at worse than Nvidia power usage; with it over time improving in performance just not fast enough to keep pace with Nvidia's steady execution of releases), and as ever people have to decide on performance for the price (including if mining throws perf/$ way out of whack for gaming). And then we get the extended cesspit of nonsensical arguments (one I particularly like is the person that went around saying that AMD needs to stop making good mining cards, then when nVidia allegedly is working on versions of cards more suitable for mining than their consumer ones says AMD completely failed by not providing miner cards before, but either way they deserve to go out of business because AMD hasn't been releasing the magical unicorn Bitchin Fast 3D 3000 that does 16K 1000Hz VR in infinite colorspace for $200 in quantities such that people can buy 2, one to use for mining 24/7 where it'll pay for itself off after the first minute that you mine on it and the other so they can game). Only instead of people learning from how things have gone, we get people just taking all the rampant speculation and treating it as reality, thus further distorting their expectations and arguments. Seems like this place is due for another meltdown.