Can I jailbreak my IPhone 4?

I tried it earlier using red snow and it didn't work and someone told me in a forum that they patched jail breaking in the 1.6.3 iOS update? I was wondering if you still can do it and is there a way for me to downgrade my iOS and use an older version?

There's always a way. Just keep googling around and watching youtube, checking for links to jailbreaking softwear. Someone will figure out how To bypass a block if there's one