[citation][nom]afrobacon[/nom]I personally like the feature. Sure it's not invented by Google Labs, but not all great ideas are...Call me old and set in my ways, but Gmail is the only email I can really stand to use on a daily basis. Anything Microsoft makes me think twice before using it, Yahoo always felt cheap to me; not to mention they remind me of the ask.com toolbar.[/citation]
It is an email program not as if you are installing a new operating system. You try it out if you don't like it you don't use it.
I always used gmail until I downloaded Windows Live to give it a spin with Windows 7. I couldn't imagine going back. I used to have to forward my university email to my gmail account but now I just sync both of them and can view their inbox/outbox separately on the same page without worrying which email came from where. The user interface is, in my opinion at least, better on WLM than on gmail but that is up to the specific user.
There isn't much to lose from simply giving it a try because it is pretty feature rich, free to download, easy to setup with gmail accounts, and easy to uninstall if you don't like it.