Bass trapping - corners or walls?

I treated my listening room with pretty good results.  I agree with auxinput's comments.  I will add the following.  Before you do anything, download REW (room equalization wizard software) and optimize the results around the room without treatment.  Get your speakers and your listening chair optimized, then play with the location of other furnishings that may be in the room.  While you are doing this, listen for improvements in vocal clarity and stereo image.  After all of this is done, then begin judicious introduction of room treatments.  As auxinput indicated, it is usually good to focus on the tricorners first.  You will almost certainly find that the measurements show accumulation of bass in those corners.  Also, be patient, and let your ears be the final judge.  Don't get fixated on ruler flat response.  Be reasonable.  I've been told it is hard to do better than + or - 10 dB in a room that is not custom built for a stereo room.    The next time I move, I intend to custom build a home with a room designed for listening.  That will be a fun project!  

Anyone have any experience with the SR black box?  I'm thinking about trying one of these in my living room where room treatments aren't going to be permitted by my beloved.

@folkfreak , thanks for the info.  I don't have, and won't have, any other treatments in the living room.  It is too alive.  No carpet.  Hardwood floors and lots of windows.  The room has almost no symmetry, so I wouldn't think room nodes would be that bad.  One of these days I will run REW to see what I've actually got going on.  Without measurement,  I think it is excessive decay time that is causing my problems.  I guess I should look for a vendor that is OK with returns.  I don't want to run a $2K experiment.