Mankind loves to obsess over numbers, statistics, and data. Ok, maybe not everybody is stuck on tracking every last thing that happens; but if you're reading this site, there's a good chance you're already checking your monthly activity reports each time Google fires off an email reminder. That addiction to numbers is about to get much more interesting. Google is merging the monthly activity report with Dashboard to produce a super-sized page full of facts and stats about how you're using Google's services.
Very little has changed about the activity report since it launched 2 years ago. There has only ever been a handful of sections, and since updates were on a monthly schedule, the information wasn't exactly up-to-date. On the other hand, Dashboard has been around much longer and offers significantly more current data, but it didn't always have the best summaries.
The content exposed by activity reports has been distributed among the related sections in Dashboard, which should include: Account, Calendar, Gmail (not showing up currently), Web History, and YouTube. Each of the summary sections will represent your usage of those services over the last 28 days. Unfortunately, there's no way to adjust the dates or length of that window - it will only display the most recent 4 week span of activity.
There is one casualty to this merger: the total history of monthly reports will cease to exist on May 31st. If you're interested in keeping that data for your records, hit the Activity Report page and make copies of everything that matters to you. If you're worried about forgetting to check your stats regularly, Google still offers an option to continue receiving monthly reminders via email.
If you've never actually checked out Dashboard before, it's well worth bookmarking for future reference. It's hooked into almost every Google property and offers direct links to many hard-to-find configuration pages.