So rc3 was smaller than usual, and now rc4 is a bit bigger than usual.
However, it's not outrageously so, and the reason for it all is fairly clear: the networking pull just missed rc3, so it's all in rc4 instead. That, along with the media pull, accounts for the bulk of the changes (the networking side has more commits, while the media side has more lines changed due largely to some SVG work in the documentation).
In fact, the media changes to the SVG files are so dominating that the diffs for this rc are 90% in Documentation/media. That's partly because everything else is really pretty small. So there may be a few more commits than usual, but they really are not all that big and scary.
Aside from the media and networking changes, there's some amdgpu updates, some scai styff, an ext4 update and some architecture updates. And misc noise. The appended shortlog gives a good condensed flavor of the changes.
Anyway, nothing really stands out, and while I really hope that we'll see things calm down further, everything looks pretty much on track for a normal release.
So go test things out. By now it should really be pretty safe.
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