Throughout the flash forwards of "Through The Looking Glass," season three's game changing season finale, Jack was distraught due to a piece of a newspaper. The bits of the article that appear readable to the viewer are as follows:

"LOS ANGELES
Man found dead in
downtown loft

The body of Jo -------------------- antham of
New York was discovered shortly after 4
a.m. in the ----------------------------- of Grand
Avenue. Ted ---------------------- man at The
Tower --------------------------------- head loud
noises ----------------------------- antham's loft.
---------------------ftey, he co ----------------------
-------------------------------------- discovered the
-------------------------- entered the loft a beam
in the -------------- room -------- cordin ----------
-----------------------------------------------------------.


While the above is all we are able to make out of the clipping, this was posted on the Fuselage (if anyone has the link, please add it), reportedly by a LOST staff member. Take it with a grain of salt until further confirmation appears (as of 05/11/08 no confirmation one way or the other has):

"The body of John Lantham of New York was found shortly after 4 am in the 4300 block of Grand Avenue.

Ted Worden, a doorman at the Tower Lofts complex, heard loud noises coming from the victim's loft.

Concerned for tenants' safety, he entered the loft and found the body hanging from a beam in the living room.

According to Jaime Ortiz, a police spokesman, the incident was deemed a suicide after medical tests. Latham (sic) is survived by one teenaged son.

Memorial services will be held at the Hoffs-Drawlar Funeral Home tomorrow evening."

Theories:

I believe it was Michael. He is survived by a teenage son Walt his only surviving relative who hates him for leaving his friends and dog on the island so wont go to his funeral but is his father so wants him to have a showing out of common decency.
Michael was an artist and living in a loft, of course, is very typical. He also would have changed his name since Ben told him he could never tell anyone about the island.
You will also notice that The (sic) Latham, not Lantham. Later John Latham was an artist from Zambia that died in 2006 and he and his wife devised the idea of 'flat-time', based on the theoretical physics of Event Structure.
Michael was 1 of only 3 characters from NY. The others were Rose and Bernard from the Bronx. (Source : htttp://www.lostforwordsforum.googlepages.com) (lostforwords)