why upgrade kernel?

[dzpost@dedekind.net]

I have a couple of machines which I'm in the process of upgrading to
Sarge.  I'm wondering about whether to upgrade the kernels.  They're
all running some version of 2.4, which I've built for the particular
machines.  If I don't get new hardware which need newer drivers, and I
don't care about any of the fancy new features of 2.6 (whatever those
are), is there any benefit in upgrading the kernel?  Will newer
versions of some packages eventually need a newer kernel?

Thanks in advance for any opinions.

-David