Gordon Baker of Algonquin Outfitters wrote to let me know that they are posting regular snow/ice updates, including pictures from many of the lakes in Algonquin, on their blog:
"We have started regular ice-out updates on the Algonquin Outfitters blog. I have posted links to your site in a few places. As of today, there are relatively up-to-date pictures of the ice situation on major lakes on the Hwy 60 corridor, including Canoe, Smoke, Cache, LTR and Opeongo."
The latest update is from last Thursday, April 10th -- definitely worth a look.