I wouldn't rush into buying first-gen product releases, personally. Always full of teething pains, issues, and design flaws which later revisions correct. New memory technology looks great, but tradeoffs and drawbacks are not immediately apparent. I'll let others pay royal sums to beta test new hardware before I buy, lol.
AMD's roadmap statements are always cryptic, but they have admitted that refinements and revisions of proven 28nm GPUs will continue to be their main revenue staple throughout most of 2015. Next-generation AMD cards built around a new GPU design and smaller fab node won't be available until Q2-Q3/2015 at the very earliest, and these will represent only a few of AMD's highest-end cards until well into 2016.
I think this R9-390X is just the latest incremental tweaking layered onto ye olde R9-280X, HD8970, HD7970 designs - so I expect "ultra-enthusiast" performance gains to be as decidedly unspectacular on the 390X as it was with each previous rebadge. And I think AMD reluctantly revealed this card earlier than planned as a half-panicked next-day response to NVidia's TITAN X announcement - AMD usually rolls out whole product lines spanned across every market segment so they can sell more of their underspec silicon yields, announcing a single enthusiast product (while hinting at another) is not AMD's style. AMD is just not in a position which allows them to take too many risks, a lousy new product would shake consumer confidence (in this niche) more than AMD can afford.
I hope I'm wrong. I like uber performance, I like more options, I like competition-driven prices.
"All opinions are not equal. Some are a very great deal more robust, sophisticated and well supported in logic and argument than others." - Douglas Adams
[/Korth]