Is it safe to remove old libs in /usr/lib?

[Anton Karpov]

After many years of upgrades (probably starting from 3.3 or 3.4, don't
remember) my box has a lot of old libraries in /usr/lib. I'm pretty sure I
have no hand-build third-party software depends on them, and with every
upgrade cycle I update all packages along with release (thanks to espie@,
it's so easy now). So I think it's completely useless in my system, only
wasting disk space in /usr. And it's safe to remove those old libs. Am I
right? It would be nice to mention it in the FAQ.