Sony didn't show much bigger stuff from own studios so it shouldn't be that hard to have at least a show as good as that from Sony. Show a few bigger third party games and Halo, Forza+ one more first party game and you have shown already the same as Sony did.
Sony did also show the console the first time which MS can't do anymore but that shouldn't make the conference worse.
Edit: MS's problem might be that they will show us third party games which we will see already the next weeks shown by the publishers themselves. That might be a problem with having the show so late.