'Page not found' but hook_menu() is correct!
If you're getting a 404 it's due to one of the following:


You haven't cleared Drupal's cache since you implemented the menu item, OR
Your event_load() function is returning FALSE/NULL for the provided ID, OR
The function event_load() doesn't actually exist


Judging from the rest of your function/file names (events_view, events.pages.inc) your module is called events so your router load function will probably be called events_load() (note the additional s).

If that's true then you need to change your menu item to match that:

$items['events/%events'] = array(
  // ...


And clear Drupal's cache to pick up the change.