As you may have recently read, the Wax Pack Gods site released an e-book entitled The Ultimate Guide to Baseball Cards on the Web. It is available for free as a download on their web page and you can also scroll through the e-book's contents on their web page.
It is a treasure trove of information about baseball card blogs and baseball card reference information that you may not be aware of. They have a very comprehensive list of the leading trading card blogs (and a few I had been missing out on) and Heartbreaking Cards gets a mention in there as well (check out Chapter 6)! It looks to be a great resource for collectors discovering baseball card blogs and for those returning to the hobby after a long absence.
It is sort of a who's who of all the different types of blogs out there from set specific ones to general card diary's like mine. It's also a great tool and everything you need to know if you want to start a card blog of your own. Check it out!