This is not the first occurrence that a critical update is released shortly after a major version upgrade of the web browser. Similar updates had to be delivered after the release of Firefox 9 and Firefox 8.
Firefox 10.0.1 fixes critical issues that came to light shortly after Firefox 10 had been released to the public. This includes at least one startup crash when the browser is opened by the user, and one Java related issue that is causing text fields to hang in the browser. Firefox users can resolve the issue manually by minimizing or resizing the browser. The patch released later today will fix the issue permanently though.
The product planning summary lists additional issues that the developers are currently looking into. This includes issues with AVG’s SafeSearch extension that is blocking the enter key. While it it possible to click on the go button to be taken to the site, it is a issue that the developers want to resolve as quickly as possible.
Other issues mentioned in the summary are additional crashes, and incompatibilities with Norton products and RealPlayer Video Downloader.
The release is already available on the Mozilla release ftp server and on third party download portals such as Softpedia. It is likely that the new version will be pushed to all users later today. At that point it will also be offered for download on the Mozilla website and as an update in the browser.
Please note that both the standard Firefox 10 build and Firefox 10 ESR will receive the update to Firefox 10.0.1.