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The main characters of "Grey's Anatomy" found moments to take their own pulses during the two-hour season finale Monday night. In thoughtful monologues, they articulated the most troubling questions of their lives — from metaphorical matters of the heart to real, medical ones.

But while the show offered a compelling window into the psyches of Seattle Grace's surgeons and interns, they also chose to wait until the finale's closing minutes to address the long-simmering love affair between Derek Shepherd (Patrick Dempsey) and Meredith Grey (Ellen Pompeo).

(Spoiler alert: Read no farther if you saved this episode for later viewing.)

Shepherd and Grey shared some long-deferred, passionate kisses — and she misplaced her underwear in the process — but the outcome remains far from clear. Echoing last season's cliffhanger ending, which found Derek cornered between Meredith and his newly arrived wife Addison (Kate Walsh), this season wrapped up with Meredith caught between Derek and the much safer choice, her veterinarian boyfriend Finn (Chris O'Donnell).

Fans might have preferred that she and Derek truly get together. But given the soul-searching journey that she's taken in recent episodes, Meredith's confusion felt genuine.

For Izzie (Katherine Heigl), things were much more definitive. After risking her career to get Denny Duquette a heart and accepting his marriage proposal after he survived transplant surgery, she returned to the hospital to find he'd died alone. "An hour ago, he was proposing," she said, dissolving in tears. Izzie didn't wait to find out whether she's being cut from the program: She simply quit.

"I thought I was a surgeon," she said, "but I'm not."

She came to that realization after stopping Denny's heart to qualify him for the transplant. As her friends rallied around her, it was clear why doctors have to first work as interns: The four resembled kids trying to regurgitate a textbook full of facts, throwing all kinds of medications and treatments at Denny to keep him alive.

"A sane person would run," Cristina told Izzie. "A sane person would marry me," the barely conscious Denny interjected.

The episode underscored the main message of the show: No matter how dedicated they are, no matter how obsessed with professional success, surgeons can't check their feelings at the hospital door and become mere technicians of the body.

"Grey's Anatomy" has always been a master of the quiet moment. Season finales are often bigger then life — using velocity to carry viewers into the next season. "Grey's" scored not only with medical drama, but with the intimate moments in between.

While each character has evolved, George (T.R. Knight) has taken the longest — and, arguably, the most difficult — journey. He began the season as a jumpy, love-struck puppy with a bad haircut and ended it as the closest thing the intern program has to a true physician. Plus, he has an intensifying relationship with the intimidating Dr. Callie Torres.

Burke (Isaiah Washington) spent the episode in a hospital bed after being shot and coping with the possibility that his operating hand might no longer function properly. Cristina ( Sandra Oh) fought her cut-and-run instincts and finally came through for him after Richard (James Pickens Jr.) all but challenged her to retain her humanity.

Richard's interrogation of the interns was a series of deftly edited series that could have come across as hackneyed, but didn't. In each miniature therapy session, with a minimum of dialogue, the characters defined themselves in stark relief and offered viewers a snapshot of who they are after two seasons of evolution.

Left for next season: Will Derek leave Addison for Meredith (effectively the same question that began the season)? Will Alex ( Justin Chambers), who showed a burst of sensitivity to Izzie in the waning moments, reunite with her in the aftermath of Denny's death? What will Cristina's feeling of losing her "edge" do to her professional ambitions — and to her relationship with the recovering Burke?

And finally, what will happen to Izzie? Will "Grey's Anatomy" follow in the footsteps of its sister Sunday-night show, "Desperate Housewives," and shed a popular main character?

It all may be beside the point. For "Grey's Anatomy," it's always the questions that matter — even more than the answers.