I like this idea, and I’d like to throw in a possible solution for the little dilemma….
Just indicate which month is being displayed in the box (Categories – February 2009), and decide which month is shown simply by determining which month has the more visible daily boxes on the screen. As you’re scrolling down, the number of daily boxes for the next month increments by 7 for each week while the number of boxes decreases by 7 per scroll… When the number of boxes for the next month is higher than the one for the “current” month, you change the values to the “next” month and it becomes the current one.
For February for example, currently you’re seeing 28 boxes for february, 14 for March. Scroll down once and you have 21 for Feb, 21 for March (when equal keep the current one), and then you scroll down again you have 14 for Feb and 28 for March – then you change the active month to March, display this in the summary on the left, change the background colors for the boxes and such (don’t forget the month drop-down on the top).
What do you think?