Isla isn't popular yet, but it is trendy. Any name that comes out of nowhere to land at 623 in the stats is a name that's on many people's minds. There are a lot of things about Isla that make me think it's on the verge of becoming overly popular. It's a "bell tone" name that fits right in with Miley, Tayla, and the rest, it has a celebrity reference, and it's part of the Irish/Scottish name trend.
Anywhere name loving people gather to talk about names, Isla has a lot of fans. I don't get it because I don't find it attractive.