We recommend you to wait a bit with updating your cracked iPhone to the new version to avoid any unpleasant consequences.
Besides, the iPhone Dev team has already provided a screenshot of what they claim to be the v2.0 firmware running on a jailbroken iPhone. Here we can see both the official App Store and the unofficial third-party application solution Installer.app running side-by-side. Moreover, the handset operates on an unsupported carrier, which is great news! Hurray!