It's allegedly at http://progend.blogspot.com/ but no longer. I checked out the URL to see what I've missed since I stopped frequenting it in December, and...
It has been removed.
This surprises me. Progression Enhanced was a fucking awesome blog, and its blogger, some bloke by the name of Sam.. Sam was a cool dude!
RIP Progression Enhanced. You were a great blog, a testament to prog blogs everywhere.
I'm gonna do some more research on this.