So I am currently running the Gmail 2.0 code. The contacts are probably the best feature, it works beautifully.
Here is a screenshot of it as it looks on my account. Also you can edit a contact right in the mail message. Which is awesome especially give that many people embed their information in the email but you don’t want to either right it all down, or open up a new tab and change their contact info by glancing back and forth. Instead you can change the user’s info right there inside of the info.
The new version is also fast, I have a pretty slow connection and the load times especially for emails has increased a great deal. One of my many reasons to use Gmail is because it has always been faster than Hotmail or Yahoo, and when you want to go through your emails doing it fast is far preferable to waiting the 3-4 seconds it takes for an email to load in the other two services with my current connection.
Gmail is making some really good moves lately, all of this keeps making me wonder why more people aren’t using Gmail. I would recommend it to anyone. My parents at my recommendation moved to Gmail after having to deal with changing email addresses every time they either got a new ISP or the ISP changed names.