Is oblivion like Morrowind - Master(s) first, then ESPs; load order of ESPs determined by date that the file was *last modified*?
(EDIT: And if more than one Master, date that Masters were *last modified*?)

Or is it it something else?

I don't have a specific reason, for now it's just curiosity; it's just that I started playing Vanilla Oblivion GOTY; then got a couple of Mods, then a couple more... Then UOP and the hotfix, then bought the DLCs and the UOMPs; then a couple more mods... sooner or later its BOUND to become an issue.

EDIT:

Odd. Funny.
:)

My topic was "new player player question..."; the forum changed it to "new player question". Sorry, didn't mean to offend. Is "new player" considered offensive here?

Exactly. ESMs first, then ESPs, both loaded depending on their dates, oldest first and newest last.

http://www.gamesas.com/index.php?/topic/1107788-boss-better-oblivion-sorting-software/ is an utility that manages the load order automatically - well, there's a variant for Morrowind as well.

Arkngt - FAST replay, thanks!

So all of those mod managers (I have none of them at present, hasn't been a need) - I guess they just change the file modification dates... I got a hold of a small utility that does that.

Precisely. http://www.gamesas.com/index.php?/topic/1109736-relz-wrye-bash-thread-49/ is the swiss knife of Oblivion modding. Very much recommended.