There's little here to report, of course, other than that this new build of Windows Phone added some under the hood APIs and support for newer devices (of which the 630 is one).
Of particular note is that the virtual Windows Phone controls on the Lumia 630 still don't have any capability to be swiped away and they still don't auto-disappear in most applications when needed, so there's clearly more to come. Watch for an update that addresses this rather fundamental issue in a month or so.
Of course, it's possible that users in the target budget market might even be confused by controls which are there one minute and gone the next, so maybe - just maybe - there's a design decision here. But for anyone with any awareness of what's possible - or even experience of virtual controls on Android smartphones, the fixed nav bar in the Lumia 630 (at the moment) looks rather restrictive!
If you have a Lumia 630, the update should be offered automatically - if it doesn't check manually in 'settings/phone update' etc.