At least for my area, I just have to scroll down to the bottom of the page and there are the packages at non-introductory rates. As well, in the small print, for the packages for new customers is the standard rate after the introductory rate is over; in most cases you can adopt any of the packages, its just a matter of what rate you'll pay and for an existing customer it will be the rate that is in the small print for after the introductory rate is over.
Channel Guides are another story, most people post they aren't even listed for the current COMCAST packages, and ones that sound close in their title to packages you have are less than 50% accurate. Still haven't seen this corrected, I made up a channel guide for the digital starter package in my area and e-mailed it to COMCAST, I still haven't seen a this fixed.
So if you want to find out what channels you get with the different packages, most people just can't, unlike other services available to you.
As well, if you do a comparison of the Set Top Boxes, form, function, software, etc, guess what you'll find.