I believe Earl's deal is already complete. I think his Twitter post last week was a hint on that front. I've stated, and many of you know, that Earl is a higher priority/value to the team than Sherman, so it would make sense that his deal is finished first, providing the certainty JSPC would want before finalizing Sherman.
I also believe the reason we're not hearing about it yet is because they are close to completing Sherman's deal and this is how John Schneider operates his program. I've previously referenced how Kam was handled last year as precedent to what we can expect this year. When Kam was signed to his new deal last year, a press conference was held, and JS made it a point to say he wanted Kam to have "his day in the sun." He expounded by saying that Kam was a 5th round pick who worked hard, did everything they asked of him, and he wanted Kam to get the recognition he deserved.
Sherman is in the same boat as Kam. I postulate that a press conference will be called soon to announce Sherm's extension, giving him "his day in the sun", and praising how far he's come and all he's done for the organization. I believe shortly thereafter, we'll hear Earl's deal announced in a similar manner. Unless talks hit a snag, I expect this is the order they will be announced to the public.