Not very soon. They clearly stated at least they aren't going to accept Bitcoin this year. But it doesn't mean they will not accept in the future. As far as I know, there were many rumors before as well, but it looks like manipulation.
Anyway, crypto means volatile. So at the same time market cap will increase and decrease based on investor's movements.
Rumors circulating about amazon that will start accepting bitcoin were able to provide a significant price increase, although the rumors were directly denied by amazon. it does seem like a deliberate manipulation.
Amazon is still focused on exploring what bitcoin is like and how it can impact the Amazon shopping experience.
In time amazon may officially announce that it accepts bitcoin, but not now.
Many new investors are starting to enter bitcoin so that market capitalization is increasing.