I don't like using click macros since it takes a lot of work to setup, eats a lot of macro slots, and some days I spam my keys slow. This is my super simple warrior tank 1-button macro:

#showtooltip
/castsequence reset=combat/target Devastate, Devastate, Devastate, Devastate, Devastate, Shield Slam, Rend, Heroic Strike
/startattack

I have Thunder Clap, shockwave, Demo Shout, and charge on seperate keys (shield block is on the same key as my tank heal key, and bloodrage is on the same key as my drop totems key). I do however have glyph'd the glyph that hits 2 targets with heroic strike/devastate, which helps a lot in heroics. Use thunderclap and shockwave every cooldown, they do generate lots of AOE threat.

No problems at all tanking every heroic with that button, and in fact I've tanked up to rotface in ICC10 with it too and haven't had anyone pull threat