It's wasn't as different as I may have made it sound. Without goin' into detail, t' key difference was that t' last beta really encouraged t' DM t' narrate and force t' PCs t' make t' skill checks he asked for based on t' situation at hand. Like t' example above, it encouraged more o' a "You come t' Davy Jones' locker end o' an alley, you must make an Athletics check t' climb. Now you be on t' roof, make a Stealth check t' move without bein' seen."
T' final version reads more like "Pick a couple o' skills that you know will be allowed no matter how many times t' PCs roll them but allow them t' use any other skills they have with a good enough explanation". Now, keep askin' t' PCs t' tell you what skills they be usin' t' solve t' skill challenge until it be complete.
This changed later with t' DMG 2, where it started suggestin' that you limit t' use o' some skills t' only 1 or 2 uses durin' a skill challenge and that some skills might be limited t' a certain portion o' a skill challenge.