After three years of Emma, it's Sophia's turn at the top of the class roster, joining Aiden for his third stint.

A growing Hispanic population might be credited for some name climbers on www.BabyCenter.com's list of most popular baby names for 2007, to be released Thursday. Sophia has more of a Latin or continental appeal than its proper English successor, Emma. Xavier, Sebastian and Isabella are on the rise, while newcomers to the top 100, to be released next month, include Lila, Maria and Adrien.

"It might be representing the changing face of America," says Linda Murray, editor-in-chief of the BabyCenter Web site.

But if anything sums up the Web site's latest hit names, it's a hunt for distinctiveness — a trend that has rendered the annual list way more volatile in recent years than it used to be 10 or 20 years ago, back when Michael could sit securely on his throne for decades.

Experts have seen an influx of untraditional names and alternate spellings, to the point where "unique" has become conventional.

Attracted to the look of the optional "h" in names like Sarah and Hannah, Melinda Kong, in Nyack, N.Y., named her daughter Elianah — a variation of Eliana, which means "God who answers."

"We haven't seen it anywhere else," Kong says, referring to a virtue increasingly sought by new parents.

Venturing even further into the written wild is a nascent creative use of the apostrophe. Despite a population so often bewildered by the difference between "its and it's," some parents have used apostrophes and mid-word capitalization to transform Jayden, Cameron and Devon, for example, into Jay'Den, Cam'Ron and De'Von, BabyCenter's Murray says.

Unlike the Social Security Administration's annual rundown, which comes out in May, BabyCenter categorizes names by sound instead of spelling, and compiles its list from the 300,000 new births voluntarily registered on their site this year. The Social Security list is more comprehensive — surveying millions of new card holders — but can also underemphasize the popularity of names like McKenzie that are spelled in several ways.

Last year, Social Security ranked Emily and Jacob as its top names.

CELEBRITIES MAKE, OR BREAK, NAMES

In a society obsessed with brands and labels, baby-name selections can be as fickle as the taste-making machine of fashion: Once the masses are wearing it (or using the name), others move on.

"The minute something pops up into the top 10, it's almost a don't-name-your-child-these-names list," Murray says.

Fairly common Adam and Robert fell 16 and 15 spots respectively last year, while Jayden plowed his way from 19 to 4 despite its association with the son of fallen idol — and poster child for bad parenting — Britney Spears.

Moms and dads are increasingly influenced by celebrities, says Pamela Redmond Satran, co-author of "The Baby Name Bible."

"So many have names that are really distinctive, and they're giving their kids names that are unique," she says. "You get the message that having a singular name makes you a singular person."

Now, once-favored Michael sits at 13th place, and the leading boy's name — Aiden — brings to mind a beloved boyfriend character on "Sex and the City."

An informal survey of new parents active on BabyCenter community boards reveals several names inspired by television shows: Miranda ("Sex and the City"), Colton ("The Real Housewives of Orange County"), Dexter ("Dexter") and Gideon ("Criminal Minds").

Names that become very strongly associated with one particular celebrity, however, tend to fall out of the running quickly, Murray says. Angelina fell off the top 100 list this year, presumably unable to compete with Angelina Jolie for ownership.

Of course, it's not just celebrities driving baby name tastes. Other values or personal stories — some heartwarming — shape new parents' wishes for their children.

Kayte Neal's 5-month-old son Tristan was named for the French word "triste," which means "sad." Not only did she love the name, but she was feeling sad because her daughter, born 21 months earlier, had suffered from a birth defect called gastroschisis.

"I wanted another healthy baby badly," said Neal, of Raleigh, N.C. "And true to his name, Tristan has absorbed any sorrows I may have had and has made me happier than any one person ever had before."

Author Satran says parents give prospective names tests. They ask: " 'Is this name going to get him into Yale?' ... 'Does this sound like a kid who can catch a ball?' ... 'Is this a name that's going to get invited out on a date or invited to a party?' "

Kim Stinson, of Clearwater, Fla., and her husband have a self-styled set of "rules" for naming their sons. They used the guidelines to come up with Trevor Hawk Stinson for their first son, now almost 2, and they plan on revisiting them for the next boy, due in March.

They don't name their child until they meet him in person. They Google prospective names to make sure they don't unwittingly bind the baby with a bad reputation. "I wouldn't want to accidentally name my kid Charles Manson," Stinson says.

The Stinsons reject "goofy" spellings, names that rhyme with bad words or names that are also adjectives, verbs or nouns. (Their first son ended up with Hawk in the middle because it's a family name, which is allowed to trump all the other standards.)

And the final rule? It can't be one of the top most popular names. "If I meet another Ethan or Logan, I'm going to shoot myself," Stinson says.

THE RANKING BY BABYCENTER.COM

Here is www.BabyCenter.com's list of most popular baby names for 2007. Unlike the Social Security Administration's annual rundown, which comes out in May, BabyCenter categorizes names by sound instead of spelling, and compiles its list from the 300,000 new births voluntarily registered on their site this year.

Top 10 for boys:

1) Aiden

2) Ethan

3) Jacob

4) Jayden

5) Caden

6) Noah

7) Jackson

8) Jack

9) Logan

10) Matthew

Top 10 for girls:

1) Sophia

2) Isabella

3) Emma

4) Madison

5) Ava

6) Addison

7) Hailey

8) Emily

9) Kaitlyn

10) Olivia

Join our discussion: How did you choose your baby’s name?