I didn't actually count them, I don't like typing in the post box and tend to paste from MS word into it and often paste messages into word to read too. I almost always have word and excel open on computers. In Word the wordcount of a document is listed in the bottom left corner and if you highlight a selection of text it will come up too, as selection#/doc# of words.

On the scumminess, word count isn't indicative of scumminess exactly, we just tend to use post count fairly regularly and discriminate between NM messages and normal, and I noticed virtually all of them were short with some non-NM really just being single sentences too big to fit in a title. Wordcount seemed fairer and the number was easily acquired since I'd already pasted all their messages into a document.

As mentioned, low post/word count isn't really very scummy at all, it is anti-town because smart scummers keep their heads down and low posting by townies makes that easier for them. Many players do post less as scum, so it can be indicative, but mostly it has to do with it being far easier to find scum if everyone is talking more, at least in terms of game relevant stuff. To me personally, as someone who almost always gets stuck having to drag the game to the end of Day 1, and getting accused a lot over that necessary aggression, I find low posting very aggravating because it gives me less to hunt with, either for real evidence or framing material, and it means that person isn't helping investigate and thus is dumping extra efforts and suspicion on me, since Day 1 lynches have low success rates and require serious shoving to achieve a consensus on. Needless to say I try to discourage that, which is why I almost never go after early-game aggressive players but routinely suggest post count and the like as means of lynching.