I've been using the "new hotmail" called Windows Live Mail (beta). My biggest complaint is the amount of space they use for advertizing at the top. But, I figured out a way to get around it.

First, you have to be using Firefox (or other configurable browsers). I have the Web Developer extension in Firefox, and in there, you can specify your own CSS style sheet. I just looked at the source code for the main page, found the CSS class name they were using for the advertisement and then added my own CSS like so:

.cAdBannerContainer
{
display: none;
}

Now, I get about 100 pixels more space on the screen. The only thing is I don't know how to make it so my CSS gets added to Firefox each time I open it. Right now, I have to reapply each time. If anyone knows how to make it apply to every page, please let me know.