First, the good: the app does what it says it will and makes a nice desktop calendar. It also encourages you to keep your desktop free of ugly file clutter :P The first version didnt allow you to pick which calendar(s) you wanted to look at, which was a major problem for anyone who has multiple calendars and a busy schedule.
The second version does let you pick which calendars to display, but the menu is REALLY slow. I actually thought the update didnt work at first. Staff were super helpful and responsive when I (and presumably others) requested this feature after the first version came out, and I appreciate that.
Downsides are the clunkiness of the preferences and the price. $9.99 is really steep for what this does. Its more of a $.99 item: helpful, but not essential. There are similar widges for iCal that you can run in your dock for free, so most people will look for alternatives before shelling out $10 for a convenience app.
ktthirteen about Blotter, v1.1