I've only been serious about steelheading for a year (25yrs for trout), so here's what little I think I know right now:

1) if you want to know a river, you have to spend time with it. Aside from that,
2) steelhead take the path of least resistance (especially the bigger ones) - ideally, 'walking speed' water for winter runs.
3) they hold/rest in tailouts after moving up some rapids
4) they'll stack up in deeper pools in the smaller rivers and will wait there for rain
5) they like to be safe - deep water near by, structure near by, fast/broken water nearby.
6) On a bright sunny day, if I look into some clear water and find that line where you can no longer see the bottom - i think the fish know this is a safer spot and will be holding here (as opposed to hangin out in the middle where the current is usually at it's strongest)
7) if there are large rocks and boulders on the bottom, they will use them to break the current
8) directly in front or staggered out behind an obstruction (big boulder) in the water
9) they know you are not a local, so they ignore your 'cracker' offering (:
10) current seems and the inside corner of the river bends

Well, take that as my 2 cents worth.

-Chad