The site stresses that a lot of this is subject to change, final choices still need to be made and may be dependent on what NVIDIA does next.Radeon RX 500 series features Polaris rebrands and Vega-based models. Launch anticipated in May.
Radeon RX 580 and 570 could be straight rebrands from RX 400 series
Vega11 may be the Radeon RX 590, a GeForce GTX 1070-like card with GDDR5(X)
Vega 10 to be used for Fury series, with new naming scheme. Expect it to be expensive, pricing in the $599 to $699 range.
As a bonus, the site posted a picture of the power connectors of what appears to be an engineering sample of AMD's Vega10. The blurry photo may have been taken at the AMD Ryzen Tech Day event and shows 8+6-pin PCIe power connectors.
The site also found a benchmark score of the AMD Radeon RX 580 video card in the Ashes of the Singularity database. What's interesting here is that this score was posted by someone using a real name as the username, and a quick Facebook search reveals this is a person working at AMD. The card scored 7100 in this test which is around GeForce GTX 1070 level performance.
The same user also uploaded a Radeon RX 560 score of 3300 points. Ashes of the Singularity scores are rather hard to compare but this seems to put it at a GeForce 1050 Ti-like level.