The newly released update (iPhone 1.0.1) only patches these holes. It does not offer any of the rumored new widgets or features that the Net has been buzzing about for the last week or so. (By the way, it would be great if those rumors were true, because some of the potential software updates include MMS, iChat, and LBS.) The actual sections of code being repaired are in the iPhone's WebCore and WebKit.
I connected my iPhone to my Mac as soon as I saw that there was an update. iTunes software let me know that there was an update available. It took about 10 seconds to download the patch, and then a full six minutes for the patch to be installed on the iPhone. After the patch was installed, the iPhone rebooted itself and voila, all done. There was no noticeable change in the way the iPhone's browser operates or functions. According to Wired, the update negates any low-level hacks or modifications you might have already performed on your iPhone. Since I haven't taken that chance, I didn't lose anything during the update process.
Of course, this patch is not fortuitous. The Black Hat hacker conference kicks off in Las Vegas this week. This update plugs a hole and prevents hackers from overtaking your iPhone.