With Superman confirmed to appear in at least a couple episodes of the next season of Supergirl, we're getting the first live TV Superman since Dean Cain (Welling never was Superman on-screen). Few thoughts:
1. Eeeeeeeeeeeeeeeeeeeeee
2. This means we'll get him teaming up down the line with either Flash or Arrow. This is inevitable, as is him mentioning to Arrow that he reminds him of a grumpy ally back in his own dimension.
3. Casting? Really, they should just get Brandon Routh (they've got a whole multiverse doppelganger thing going on in Flash right now; they could have Dean Cain as older Earth-3 Superman too), but that won't be happening, not least of which because they said they're casting rather than just giving him the role. Personally I'd root for Josh Boultinghouse to get the part, that'd be fun.
4. Superman spinoff show? Unlikely, but the seal has officially been broken on using him. Speaking of which...
5. While obviously the limitations might be slightly lesser with him given that he was kind of already present, if the years-long embargo on using him on TV has been shattered even though he's going to be in movies, along with Flash getting to appear on TV as well as onscreen, how far can they go now? Can they introduce Green Lantern on Flash and Arrow the way they've clearly been dying to for awhile now? Will Batman and Wonder Woman get to show up? Could we get a TV Justice League (I'd already thought they could go with Supergirl/Green Arrow/Vixen/Flash/Firestorm/Martian Manhunter/Atom as a decent TV JLA, but the options might be more open now)? The Flash show already implied that a version of the team will one day be formed. I'd also dig bringing in Justin Hartley as Aquaman; they nearly mentioned Aquaman in the first episode of Flash anyway.
In any case, we've now got a DC TV Multiverse that includes Superman and Supergirl, Flash, Batman/Wonder Woman/Green Lantern by implication, Green Arrow, Firestorm, Atom, Rip Hunter, the Legion of Superheroes, Earth-2, the JSA, Hawkwoman and Hawkman, John Constantine, Martain Manhunter, Red Tornado, and Vibe. Things are strange this days.