I'm sorry but isn't the point of live tiles is partially THE notification center for windows phone? What exactly do you all expect the notification pane to do?
I expect it to shut up all of the Android people who complain about a lack of one. Listen, as WP users we know we don't need it, so we get it to shut everyone up and remove a point from Android People who won't recommend WP due to a personal agenda.
I appreciate the snark, but honestly this isn't true. Live tiles are great for glance-able info. Temperature, number of texts/emails next appointment. This is not the same thing as a Toast notification. Live tiles do nothing if I want to see a quick list of my missed calls and texts when I was away from my phone, they just give me a number while a notification center gives me actual detail on who called/texted me and when.
Of course you can just open each app to get this, but that's more clicks and it's also not an available option in every app. The best example of the need for a notification center is the ESPN and CNN apps. Each can give you a toast with scores, updates and breaking news alerts. These toasts are useless w/out a notification center if you don't get your phone up and open in time to read them. Complicating matters further is that the WP toast bar doesn't scroll or allow any way to read the full message meaning much of the info is completely and permanently inaccessible. Theoretically each app could maintain their own record of toast alerts that were sent, but they currently don't and it's unreasonable to expect every developer to build this functionality.
It's valuable to see all toasts/alerts from all apps in a time sorted thread as well, Live tiles can't do this. The Me tile's notification center does this for inbound social updates and the people hub does it for individual contacts for calls/messages/emails under history, but there's nothing unified and there's nothing for app updates that aren't tiled to an account record.
Also it's worth noting that Live Tiles have an inherent issue with displaying text of more than 6-8 words is a easy to read format. An issue exacerbated by the addition of extra small tiles.