I don't think it can be tagged as rumor, or gossip anymore, as hey the XT models we talked about last week, are listed as AMD Ryzen 9 3900XT, Ryzen 7 3800XT, and Ryzen 5 3600XT in etail.
While the processors are listed, the etailer is a bit unreal with its pricing, but still, they are listed as the 3900XT is tagged at 499€, the 3800XT at 459€, and the 3600XT at 319€, incl of VAT. Materiel.net 1, 2, 3.
The rumors indicated that Ryzen 9 3900XT would get a boost clock of 4.8 GHz, and that is 200 MHz more than the 3900X model. Importantly though the base clock would be also be modified to 4.1 GHz and that is a 300 MHz faster than the existing model, these would be significant changes:
RYZEN 9 3900XT - 4.1GHz base, 4.8GHz boost.
RYZEN 7 3800XT - 4.2GHz base, 4.7GHz boost.
RYZEN 5 3600XT - 4.0GHz base, 4.7GHz boost.
RYZEN 9 3900XT - +300MHz base, +200MHz boost.
RYZEN 7 3800XT - +300MHz base, +200MHz boost.
RYZEN 5 3600XT - +200MHz base, +300MHz boost.
We can't wait to tell and see how much the extra performance will benefit AMD, especially with comet lake released we could see that 3900XT and 3800XT competitively against the i9-10900K and i7-10700K. It's rumored that these procs will get announced (not released) in mid-June, with availability in July 2020.