This is a deliberate move on the part of Comcast. There is really no good way to go directly to your Inbox in the webmail portal. But you can avoid the Comcast Preview page entirely if you use an email client program like Outlook, Windows live Mail or Thunderbird. That way, you don't have to look at any of the Comcast pages to get to your email, and you don't even have to be signed in to your Comcast account.
Sorry, but that is the reality of the situation.
There is one Comcast page that will take you directly to Xfinity Connect without going through the homepage.
This could change in the future.
The only other way to go directly to email is by installing the Xfinity Toolbar. Personally, I don't want the toolbar (or any toolbars) but for those who like them it could be an option.
I use an email client and rarely look at the homepage, which is nothing more than an online version of a bad supermarket tabloid.
Cant you go to this page, it has my inbox: http://web.mail.comcast.net/zimbra/mail?app=mail#1
The link takes me to the homepage. Which has this at the top of the page
Your XFINITY Connect session has timed out due to inactivity. Click here to go back
Well, duh, there has been no activity with Xfinity Connect. It's been several days since I've looked at it.