These posts are always hard for me to do, because I'm an absolute idiot when it comes to this technical stuff. I'll do my best to make a summary that's sensible, and if I mess up some terminology, please feel free to hit me up with corrections.
Recently we saw that dataminers found some interesting info in the latest Switch firmware update. The juiciest tidbit was info that pointed to a revision of the Tegra 210 that the Switch currently uses. Long story short, evidence points to the Switch using the Tegra 214 in an upcoming revision, and this was thought to be in response to a bootrom exploit. It seemed like the story started and ended there, but now we have rumor of even more revision evidence surfacing.
The latest snooping brings out rumors of further revisions in the works for Switch. Supposedly there's information that mentions both a bump in RAM, and a new PCB. The Switch currently has 4GB of RAM, and the revision would double that, making for 8GB total. As for the PCB update, we don't have any concrete info on what it would be upgraded to.
Again, all this is just rumor and speculation right now, based off of datamined info from the latest firmware update. Even if a revision is in the works, it could be something that's for dev units only, and wouldn't make it into retail versions for consumers. Only time will tell, and as I've said before, Nintendo's not usually one to trumpet tech specs of their hardware to the public. If these changes do get implemented, we'll likely find out from consumers opening up their Switch units to see what's under the hood.