[chipper57AA]

The only online "tell" that I've seen on occasion is where you see someone betting or raising instantly without hesitation.

This may indicate a couple of things.

1) The guy currently has top pair but if any overcard comes up he may be at risk - so he bets or raises quick to try to scare out a drawing hand.

2) The guy has the nutz or a great hand and is not afraid of anything.

3) The guy is on a major bluff and a fast bet or raise is trying to intimidate you into folding.

Hard to say really as it could be almost anything. As the others have said, you have to take into consideration how the player has played in the past.

I'd hesitate to read anything much into how fast someone bets. Some may just be taking their time to analyze a hand, or sometimes they are not sure about their hand.

Basically, stick to good poker strategy and bet when its strategically good to do so.