Here's a couple of comparison images, straight from UT.
They supposedly added some scenes, too.
Indeed there are additional scenes. I remember back when the first episode aired, some people were complaining about them cutting out the "park-scene", which at the time I had no idea what they were referring to... Said scene is in the BluRay-version however. Episode 2, 10 and 12 also apparently have new scenes in them.
And that comparison... You know, watching the broadcast version I always thought that shot of Archer firing at Caster in the opening seemed weirdly dark, and when I saw the BD-version, where the white parts of his projectiles actually WERE white, I figured, okay, so the TV-broadcast was darkened in places to accomodate broadcasting standards. It looks so
much better on the BDs though.