Windows XP full-text search was a back-ported version of Windows 7 search. It was a regression from Lookout (Microsoft Acquired) but an improvement on Windows Live Search. The UI adapted to the result type, so Appointments showed different attributes than Contacts or Files.
Windows 7 Search is another regression, and a big one. When I hit Windows-F for example (only way to really use it), and use Details view (best view), my Outlook Appointments (meetings, etc) show with 'modified date'. That is not particularly useful.
Fortunately there are workarounds. I don't think they are well known, even after I figured this out I couldn't find any posts on this.
One work around is to switch from Details View of search results to Content View (control is a drop down in the explorer bar - right side). Content View shows attributes appropriate for the data type. Enabling the preview bar and you get something like the XP search interface - albeit without column sort or sub-search and, inexplicably, some standard objects can't be previewed on my machine (tasks?).
Alternatively stay in Details View, but right click on the columns (Name, Date Modified, etc). This will produce a very long list of attributes/columns that can be added. For appointments you want "Start date" and "End date" (if you don't know the name, good luck finding them). You can change sort order. You can add selected attributes for other items of interest. The result for many searches will be a sparse matrix, but you can sort by the columns of interest.