GL's still viable. Like KT said, if you run into one of his bad matchups you're possibly fucked...thankfully these matchups are also a rarity in the first place. Plus he deals with a lot of the more popular characters well. I've said this before...numbers-wise he seems unviable and not top 10, but in reality that's not the case due to character popularity.
His "gimmicks" are being figured out, but his strongest aspects aren't even the gimmicks. His neutral game is solid...once he reaches a certain spot on the screen, just about every character is left being forced to respect his options. On top of this, his oki offense is good (no it's not bad if you're not just doing f3 all the time). b13 is backdashable, but GL has too many ways to go about using b1 that you can't just backdash and be like OH I PUNISH JOOZ!
He's still good. Just less fraudulent by way of the metagame development.