First, Warehouse 13 is coming back April 29, but the season premiere (the resolution of last season's cliffhanger) is currently available online via the SyFy web site and OnDemand (depending on your cable company). I watched that last night, but I may have to rewatch the older episodes they've also put OnDemand because I'd forgotten a lot.
I also watched the series premiere of Defiant, the new SyFy show. I'll definitely watch it again, but I'm not in love with it yet. I've found that the shows I get really into have some character or some question (or some question about a character) that makes me eager to see what happens next, not so much for the plot but because I can see that the mix of character and situation is going to be interesting. A lot of it comes from a sense of surprise. For instance, one of the things that got me intrigued about Firefly when I saw the first episode that was aired ("The Train Job") was the revelation that on this ship full of criminals pulling off heists, the one who was wanted by the Feds was the prim and proper doctor. I remember that sense of "Oh, now this could be interesting." So far, there's none of that in Defiance. I don't dislike it, but there was nothing that had me really curious about how things would work out.
From what I could tell of the backstory, there was an alien invasion by an alliance of races that planned to terraform earth to be a new home for them, but they weren't prepared for earth already being inhabited. There was war, until the soldiers decided not to fight anymore, and now there's a tenuous peace in a weird postapocalyptic landscape. Our Hero is a Mal Reynolds/Han Solo type, a former soldier who's an embittered veteran of a famous battle who's now something of a mercenary/scavenger, and he travels with his adopted alien daughter, a war orphan he took in and raised as his own. They get robbed by a roving gang and then are rescued and taken to the town of Defiance, formerly known as St. Louis, and if you've ever seen any movie or TV series ever, you pretty much know everything that will happen after that.
It has a bit of a Firefly vibe, with the Western tropes in a science fiction situation, and there's a dash or two of Mad Max in there, as well. I find a few of the characters interesting, though not all that intriguing (there's no real mystery to any of them, nothing I'm dying to find out). I'm a little worried about the teen Romeo and Juliet plot because the kiss of death for most of the recent science fiction series (V, Terra Nova, Revolution) has been the annoying teens put front and center. But my main problem with the pilot was that there were no surprises whatsoever. Starting about five minutes into the show, I had outlined pretty much what would happen. A lot of these tropes are right out of famous movies, down to the scenes and even some of the lines. Even the big "shocker" in the episode's tag was a bit of a "well, duh!" Granted, I'm hard to surprise because I know too much about story structure, but it would be nice to have one or two developments that I didn't see coming or that didn't seem so horribly telegraphed. I feel like I can even see how the series is likely to progress, so I hope they throw in a few monkey wrenches along the way to shake things up. Maybe the obvious triangle won't happen or the obvious budding relationship between the currently at-odds younger people won't come about, but I won't hold my breath. Still, it's science fiction on television. There are spaceships and aliens, and so far the teens aren't too prominent, so I'll be watching unless something else gets in the way.