Google is gradually rolling out some changes to the look and feel of their products. In Google calendar you can "opt-in" to the new look by clicking on the gear icon in the upper right and selected the link titled "Try the New Look".
As an example of the changes, compare the selection of calendar ranges (day, week, etc) on the upper right in the old "classic" view.
as compared to the new look
For more on the changes that should be coming to a calendar near you in a few days (if not already there), read this blog article from Google.
Beyond look and feel, you might try the "speedy meeting" setting in your general calendar settings area (also available via the gear icon) and checking the speedy meeting checkbox. 25 minutes of meeting time is reserved for half hour time slots and 50 minutes for one hour time slots. This gives your guests time to get to the next meeting.