The reason they are nixing Eureka basically comes down to the contracts for the actors: Around the 5th season, most contracts end and the actors get to renegotiate, usually for more money if the show is doing very well (which it is). SyFy operates it's shows on a shoestring budget and isn't willing to pay the actors any more then they are getting, mainly because the shareholders and executives are idiots. This is one of the reasons they only wanted to do a half season to finish out the series; they liked the series, the actors and the ratings, but couldn't justify the increased cost per an episode to the money people.
This is a common trend in TV. It's why most shows don't break the 5 season barrier. You really need to be a big name show and be bringing in mad money to get past 5 seasons. Unfortunately, this is CABLE and cable doesn't bring in the money.
That being said, I suspect that you'll see Neil Grayston (Fargo) bring his character over to Warehouse 13 since the two shows share a universe and he's done two cross-overs already. He'll likely become a regular once Eureka is over. But that doesn't matter... come 2014-15, Warehouse 13 will suffer the same fate as Eureka.
Am I going to miss Eureka? Yes. It's one of the few shows on TV that reminds me of the Roddenberry-era of Star Trek*. Not the science stuff... but the sense of hope and optimism in the future that the shows demonstrated. They (and by extension it's writers) believed in humanity and it's accomplishments, both good and bad, and that we, as a society and species, could one day become better than we are. Most shows about Science Fiction only dwell on the dark of it, about the problems that it can lead to... but Eureka was the first show in at least a decade that pointed out that sure, they are going to be problems along the way, but that one day we might make a world we could actually be proud of and that it's going to happen on the frontier of Science.
It's become especially poignant this season: The year that NASA decommissions it's last shuttle is the season that Eureka launches it's own mission into space. In a time that has decided that going into space is too expensive, too dangerous, and ultimately not worthwhile as a government goal, Eureka tells us that there are untold wonders beyond our planet and that it's more than worth it to look for them. That's something that speaks to me and I'm going to miss the show all the more because of it.
*And I'm saying this even though I vastly prefer Deep Space Nine.
Every time I'd sit down to watch the start of a new season, it felt like coming home. You'd see all the familiar sights and characters. It was like watching a new Harry Potter movie.
