Google Trends [0] indicates that sqlite is about as popular as usual. There's been some recent growth in the last year, but that's after a bit of a dip. A regression of the time series would be fairly flat.
I suspect popularity here comes in waves through a Katamari Damacy effect. People start reading about a topic, and start posting, thus more people read, research, post, etc... until a saturation point, a cooling off period, and then a rebuild.
[0]: obviously not the same as whats happening on HN, I'd love to see someone pull these numbers from the HN API!
They were talking about it being a fad here on HN, in terms of submitted (and upvoted to FP) posts per week/month/year. It's always been a topic getting the incidental FP attention, but the number of times something relating to SQLite makes it to the front page here seems to have increased considerably in recent months.
