Here is my take on Internet Explorer:
1. Tabs are great, even though I miss the rounded corners from Firefox and Flock. Interesting, I guess Flock doesn't have rounded corners for the tabs. There is something I don't like about the way IE7 renders the tabs. Maybe because the tabs are sharing the same horizontal space as the favorite tools and all menu options, the user is really left with only 2/3rd's of the space for tabs.
2. Integrated RSS is more impressive than Firefox. IE parses an RSS feed showing a 'subscribe' button towards the top which is very nice for non-techies. However they dropped the ball on placement for retrieving the data. You need to go to the favorites section and click on the RSS tab. RSS is an important feature of the new web and should be a big button on the task bar.
The second issue with the RSS feature was the lack of quick navigation through RSS feeds. I subscribe to 40 odd RSS feeds through Bloglines and need an easy way to get my information fast. I couldn't even begin to use IE for RSS reading. It kinda reminds me of Firefoxes built in RSS engine without the live updated bookmarks, but Sage is a much better platform for consuming information.
3. Third gripe, when running Windows Updates, all other tabs are not available. I'm pretty sure that IE6 used to allow other windows to grab focus but tabs are a different story. Luckily, I could open Flock while waiting for IE7 to download updates.
4. Bloglines renders the left pane in a minor funny way under IE7. This is probably to be expected since IE7 hasn't left beta but I am quickly reminded that IE7 probably doesn't follow Internet standards.
5. I did, however, like the minimized interface of the address bar. My first impression was rejection but after forcing myself to not change the interface to the old skin, I started liking it.