Greasemonkey is a powerful addon for Firefox, it allows you to make your own JavaScript-code to execute on an arbitrary website, and in conjunction with its powerful APIs, you can manipulate every homepage you want in any fashion you see fit.
I've created a script which displays the amount of comments your Google Video uploads have on your status page, and if there are any new comment since your last check, it will add a nice new! text in that video's column. The script is licensed under the GPL. Install the script here. (Hover your mouse over the image to see a bigger image)
You can also see the comments made to each of the videos by clicking the comments column for that video! There's also an update feature (Tools -> Greasemonkey -> User Script Commands -> Update comment script), although it doesn't check automatically.
The script now displays the number of comments in the Reports tab, if you have lots of videos you should check for new comments there instead because it'll show you all the videos at once so you won't have to go through pages like in the Videos tab. The script now shows the total amount of comments as well.
2007-08-21: I've made some visual improvements that you should like.
2007-08-31: The popup displaying the comments can now be closed by clicking anywhere outside the popup.
2007-09-26: Fixed the close button image not appearing. Are anyone else having troubles with comments disappearing randomly and then appearing again? Recently about 100 comments have "disappeared" permanently from my videos... :(
2007-10-17: Changed the way new comments are detected. Now storing the internal comment ids instead of the number of comments, and then examining these ids to determine if a comment has been encountered before. This means it should handle cases where there are missing/deleted comments better.
2007-10-18: Bulletproofed the way new ids are stored.
2007-12-22: Huge code restructuring. Added fetching of total video rating. Added large size.
2008-04-24: Google updated the interface for Google Video, and in the process broke the way the script fetches ratings. Updated the code, and thanks to the new redesign the script fetches the ratings much faster!
2008-06-15: I finally took the time to update the script to fetch the comments correctly since the redesign to Google Video. Comments also fetches much faster since only one request is needed.
2008-06-20: I've added gvidcomments as a project on google code. I've released a new version which contain some minor changes. The built-in updater won't update you to the google code version yet, but I'll do that soon enough.
2008-07-05: I've updated the version hosted on this site to a version which, when you try to update again, will ask you to read this page to help you update to the Google Code version. Since I updated the namespace on the Google Code version you will have to uninstall the old version, otherwise you'll have two scripts running. Otherwise no real changes. I don't know if I'll update this page anymore, so go to Google Code if you want more information in the future.
Another Greasemonkey script that you probably don't want is schema.user.js for Novasoftware's WebViewer. Don't get it if you don't know what it is.