I just used the last page of my menu journal to write our plans for next week. I started journaling menus in September 2007 with a tad too much ambition. Initially, the intention was to write commentary on the menus, record adjustments to the recipes and comments on wine pairings. The task was too daunting and the record stops after 6 weeks. 
The journal resumes in November 2008 and continues through today. The change was that I only write our menu plans for the upcoming week, special occasions, and the source of the recipes. I always wrote my recipe comments directly in my cookbooks anyway. I use one page per week and make a list of what we will have for meals, side salads for John's lunch, contributions I'm taking to potlucks, etc.
In flipping through the journal it also reveals activities. At the top of each page I write the "week of XXX" and follow it with family plans for the week that would impact dinner planning ... Work related banquets, dances, travel plans, etc. Another benefit is that I can look back to find a recipe when I can't recall the source, which is getting more common lately.
I bought two of the same journals and will start using the new one next week.