Originally Posted by onthego15

A strategy of focusing on just one hotel program makes no sense unless your primary goal is status in that program, and even then a wise traveler will have a backup.
SPG has small number of hotels, so you may be disappointed if your travels don't take you to big cities.

I have points in 4 hotel programs right now - SPG, PC, Choice, Carlson - and I considering acquiring points in another to give me even more flexibility.