Sorry days, being a little (alright, quite a lot) more serious, don't worry about it.
As has been noted, people write in different ways, some of which may seem overly formal to you. Some of this is down to cultural differences, and some to the 'character' in which you play a game.
Personally, when on the forum (or in a non-anon game) I tend to use this rather formal style, simply because this is how I type most. After all, generally if I'm typing something its for someone else to read, and generally someone important.
Anon games, well I do my best to sound like everyone else in the game!