Looks like this flight diverted to LGA was only one of quite a few diversions. I've compiled the following flights bound for EWR this evening, which were diverted. It appears a number have since continued onward to EWR, but some still remain at the diversion airport.
Judging by the number of flights from Spanish-Speaking origins which diverted to Syracuse, I wonder if perhaps they had staff which spoke spanish, or if it was just a coincidence.
Not sure if any of these flights actually deplane into the terminal, but for those who diverted to Newburgh, there is but a small newsstand after security.
BOS
-----
103 - 757 from Amsterdam
BWI
-----
1897 - 737 from Montego Bay
PIT
----
519 - 737 from Tampa
PHL
-----
860 - 737 from St. Maartin
CLE
----
429 - 737 from Denver
ABE
-----
2579 - ERJ from Charlotte
2682 - ERJ from St Louis
BUF
-----
50 - 737 from Cleveland
LGA
-----
1827 - 737 from San Diego
SYR
-----
1733 - 757 from Cancun
804 - 737 from San Pedro Sula
1742 - 737 from Mexico City
210 - 757 from Houston
SWF (Newburgh, NY
-----
1761 - 737 from San Jose Costa Rica
86 - 777 from Shanghai
1866 - 757 From Punta Cana
1551 - 737 From Cozumel
800 - 737 From Ft Lauderdale
449 - 737 From San Francisco