State of the Comment Spamosphere

I thought it was time to revisit my tracking of comment spam, so I went through the usual process of grepping through my crawl of Akismet stats pages. The graph I produced looked pretty weird and I started to wonder what was going on with Akismet these days. So I went and looked at their stats page to see if my processing was correct or not, and there I found that they have a graph of their own - and a lot nicer than the one I was going to post. However, the graph does show exactly the same data:

Qualitatively, while Akismet looked reasuringly predictable in its first 6 months, things seem to have gone a little haywire. So - what's up Akismet? Are the spikes huge coment spam attacks?

Update: some more data on comments, this time from Typepad.

Comments

[Richard Evans Lee]

I saw a couple of spikes about two months back. One I'm fairly sure was probably from a single source. Someone had registered a bunch of finance and pharmacy domains - the kinds with lots of words and dashes - and sent wave after wave of comment spam.

Lately though the amount of comment spam my sites are getting is so low as to be trivial.