Also, both FF and Chrome say their is unsecured content on these pages.
I think your site might be a good candidate for gradual engagement. Chech out this article: http://www.lukew.com/ff/entry.asp?1128
Regarding the above, perhaps the subscription offers could be combined, so I can just start using the site and get everything for 2 weeks and then once 2 weeks is over, the site changes for me and presents me with subscription form if I come back. Right now, its hard to judge the quality of content before I sign up, even if its free for 2 weeks. Its still a barrier and makes me not want to.
On the about Us page and home page, I'd like to see more about the contributors. Quality of content on a site like yours is key, so I need to know more about who is contributing in order to get me to sign up. If you're just launching with no prior reputation, this is very important. As you get established and more known, this could probably be de-emphasized.
Think about possible redesigns for home page. Probably a good half of the page above the fold is taken up by the large Track image and the Track offers.
Adding a page that lists all our contribs is on my to-do list - definitely agree that that's lacking. I also agree that the trial needs to be more explicit, and we should probably upsell with more than just an email when the trial progresses/ends. The other suggestions you made were helpful as well.
Thanks for taking a look!
No problem and good luck with your site!