From what I understand, it is perfectly okay to film in public, but you need to get consent from anyone your filming as well as consent for business logos, product labels, etc. It's why TV like MTV has to blur out T-shirts and such.
Not sure about filming on private property though. You'd probably have to get permission from who owns the property?
Disclaimer: I'm not a lawyer and I can't guarantee the above information is accurate. Your best bet is if your confused about this, ask a lawer.