Sony announced at E3 that a PlayStation Plus subscription is needed to play online on the PS4. The sad part about this is that PlayStation Plus is still not available for all countries.
Sony responded to a user about it on the PlayStation Blog saying:
“Unfortunately at this time gamers in countries which do not have a Store cannot access online multi-player features. However, we are considering every measure to offer PlayStation Store services to these territories as soon as possible. To clarify, the affected territories are: Bahrain, Lebanon, Romania, Oman, Slovakia, Malta, Cyprus and Iceland.”
There are probably other countries around the world affected by this too. Hopefully Sony can roll out PlayStation Plus to most countries before the PS4 launches later this year.