Pretty much. Either get a 1070 or a 2nd hand 980ti on the cheap to see you through till 1080ti/Vega. 480 doesn't make sense.
Are You referring to GPU-Z info. Probably because GPU-Z is still not updated. I remember last year, few weeks after AMD add DX12 support in drivers GPU-Z still was showing for almost month my card as only DX11. The same was in windows dxdiag, it took over two months for MS to update dxdiag tool And about 290X upgrade. I will keep it or upgrade to 1070 at this moment. Anything else is not worth $ You will spend on 480, as You will see minimal performance gain if any. Only profit is probably 8GB of VRAM
I wouldn't make any decisions within the first month of launch, see how the card performs, see what new drivers bring, see if AIB cards are good, and don't forget about the fact that launch purchases are/can be beta testers and have problems with launch cards. I would definitely think about side-grading, especially if you only have a mid-range budget, but I would certainly wait a month or two to see how things go.
Not quite according to the leaks, but it seems that temperatures in the high 80s with fan spinning up over 75% (read loud) will be pretty standard.