To edit the event just tap the "Edit" button in the upper right corner.
When you tap the location you can open it in "Apple Maps", “Google Maps”, “Navigon”, “TomTom”, “Skobbler” or “Sygic”.
By tapping yourself in the attendees list you can change your response (Yes/Maybe/No). And by tapping someone else you can open that contact e.g. to call that person (if it is in your address book).
By tapping the trash icon you can delete the event.
The "Send" button allows you to send the event by email or SMS.
And the folder button allows you to save the event as a template.