The first Eleven Foot Poll has closed, and according to you readers your favourite Player's Handbook class is the Warlock.
Let's look at the Warlock. The two builds offered in the Player's Handbook are a Deceptive Warlock, who specialises in debuffs, and a Scourge Warlock, who is a straight-up DPS class.
The Scourge Warlock is a machine. In damage potential, it rocks the DPS world. Your 1st level at-will damage dealer, Eldritch Blast, deals 1d10 + Con/Cha + normally your Warlock's Curse (1d6). So for a maximised character, 1d10 + 1d6 + 5 (Min 12, Max 23, Average 13).
Compare that to a Rogue's Sly Flourish, which in most rogue builds will be doing in the order of 1d6 +5 + 3 + 2d8, assuming combat advantage, backstabber feat, and a shortsword or upgraded shuriken. (Min 11, Max 30, Average 20). Or a Ranger's Twin Strike, which will do 2d10 + 1d6 assuming two hits with a longbow (Min 8, Max 26, Average 14).
That's just damage, of course. Consider that the Warlock is targeting Reflex while getting to add their full implement bonuses, and the only pre-requisite condition for the damage is that they've cursed the target in advance. The Ranger, on the other hand, has to make two hit rolls to pull off full damage, and must also have marked the target as quarry, whereas the Rogue is looking for the never-there-when-you-need-it scenario of having combat advantage.
You really get the synergies going, though, when you look at how Warlocks use Constitution. Con is one of the two modifier stats on Eldritch Blast, feeding into both the hit roll and the damage. It also powers two of their other first-level at-wills, Dire Radiance and Hellish Rebuke, plus their best first level encounters, Diabolic Grasp and Vampiric Embrace.
A dwarf, half-elf or human can start play with 20 Constitution (+5 modifier), 32 hit points, 11 healing surges and a surge value of 8. Your basic to-hit on Eldritch Blast will be +5 (+6 at second level) and you'll be saving your gold towards a +1 implement. You can take the Infernal Pact to get extra temporary hit points every time you hit a marked target, to turn you into a genuine tank-lock, or pick up the Star Pact and designate yourself as the team's minion-killer to start rocking +1 or higher hit bonuses on most turns.
While I'm sure he's not the first, credit for discovering the tank-lock in our play group goes to Arkem, who played the character as a half-elven version of "Fat Bastard" from Austin Powers.
What about you? What's your favourite Warlock build or power?