The other approach is finding the peak of a given track and normalizing to that peak. Thus, two tracks which each peak at different decibel levels could be normalized such that their peak volumes (not their average volumes) match. [/i[

Which is crappy IMO, and has been beaten to death here before.

I see nothing about dynamic compression in there, really, it seems like raising/lowering the volume per-song... Not really Voladj-like, but more of a fixed +/- factor per song.. or am I reading that wrong?

Perhaps I am wrong. I can tell you that:
1) the normalize package is misnamed; It does dynamic range compression by default as of several versions ago.
2) my recollection (and here's where we may be losing) is that the normalize plugin for xmms provided which does rva2 does range compression and not peak matching.