Google has released version 4 of its toolbar for Internet Explorer. There are a couple of new features in this release:

Enhanced Search Box
As you type a search query into the new Toolbar’s search box, you’ll see a list of useful suggestions based on popular Google searches, spelling corrections and your own Toolbar search history and bookmarks

Custom Buttons
You can now add buttons to the Toolbar from the Buttons Gallery

Bookmarks
You can create and label bookmarks from any computer

Send To
You can use your Google Toolbar to share web pages via email, text message (SMS), or blog.

Search Settings Notifier
Google Toolbar can make sure that your default search values are set to Google so as to prevent homepage hijacking

Vie all features here