I've got a jailbroken 2.2.0 iPhone. I'm wondering if upgrading to 2.2.1 is worth the effort. If it's easy, I'll do it. If not, I'll wait until a major software upgrade comes along. So what exactly is the upgrade path here? I'm assuming the 2.2.1 firmware will replace the jailbroken firmware so I'd have to jailbreak the phone again, right? And what about my cydia apps? Am I going to have to do anything special to make sure they still work? I'm mostly concerned about the iphonemodem application that lets me use my iphone as a wireless modem for my laptop.