There's some confusion on how super stats work, so here's a little clarity.
No matter what super stats you pick, stack them as high as possible.Almost all of your damage comes from your super stats simply because they are your super stat. Sure, some of the stats give a little benefit, but the flavor of the game is that you could have a high intelligence/high presence might character and you'll still do ok.
That being said, here are the basic benefits of each stat.
Strength - Melee damage (up to +20%), knockback resistance, physical hold recovery. Helps Invulnerability and Enrage
Dexterity - Critical strike chance and stealth detection. Helps Lightning Reflexes
Constitution - Increases maximum health. Helps Invulnerability and Defiance
Endurance - Increases maximum energy and energy gain from your builder. Helps Personal Force Field.
Ego - Increases critical strike bonus damage and intangible hold recovery. Helps Personal Force Field
Intelligence - Reduces cooldown times, reduces energy cost and increases pet damage.
Recovery - Increases equilibrium energy level and energy gain from your builder. Helps Regeneration.
Presence - Increases threat in defensive role, decreases threat in support and offensive roles, increases healing effectiveness and increases pet health.
Strength, Constitution, Presence, and even Ego are good for Tanking types.
Strength, Dexterity, Endurance, Ego, and Intelligence are good for DPS types.
Endurance, Intelligence, Recovery, and Presence are good for Support types.
But most of all, have fun with it. Pick a stat that fits your theme more than what may provide you the biggest boost. Unlike picking powers, it's hard to gimp yourself by picking the "wrong" superstat.