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My understanding:
Space is expanding away from us, and every other point in the universe, at around 73.5 (+-3.2) Km/sec/megaparsec. (Hubble Constant from WMAP.)
Using that figure and the speed of light of 300000 Km/sec, a rough calculation puts anything more than 4100 (+-100) megaparsecs = 13.3 (+-0.5) billion Light Years away having expansion taking it away from us faster than the speed of light, so the light emitted will never reach us.
As objects we can see reach that distance they get red shifted to invisibilty.
Gravity holds the Local Group together more strongly than expansion is trying to tear it apart, so given long enough the visible universe will be cut down the Local Group, and maybe the Virgo Super Cluster.
How can you talk about what is outside the universe? There is no outside. The universe is everything.
Time starts at the Big Bang. There is no meaning to time before that.
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