As already mentioned several times, there are no special landmark
features or incompatibilities related to the version number change,
it's simply a way to drop an inconvenient numbering system in honor of
twenty years of Linux.
From Linus himself.
It's about time, 2.6 lasted way too long.. New version system would be cool. When configuring grub or something, it's like 2.6.what? which kernel did I just compile? can never remember.
3.1.0's been out for about a month, why have not heard until now? Stumbled upon it by complete accident.
localhost / # ls /boot
localhost / # mount /dev/sda1 /boot
mount: unknown filesystem type 'ext2'
Uh-Oh, think I fucked up somewhere.. I'll fix it, lol. Ugh! re-compile. Weird that "Second extended fs support" wasn't ticked by default, maybe accidentally removed it.