Now you can bookmark sites without using third-party tools (although some of them have more advanced features) and add custom buttons that let you search other sites and read their feeds. If you want to add a button for this blog, here's the link.
The latest version of Google Toolbar makes it easy to send snippets from web pages by email, SMS. It's also easy to have a blog without actually writing too much original content.
But the greatest news should be the last one: you can now open files from the web using Docs & Spreadsheets. You can also drag and drop files from Windows Explorer to Firefox or just associate documents with Firefox. Here's the list of available formats: .doc, .rtf, .odt, .xls, .ods, .csv, .sxw.
IE toolbar looks better, has smaller icon arrows and seems to be more stable. But don't forget this is beta software (if that still has a meaning).