Posting comments and writing blogs is now part of the daily activities of many communicators but how can you tell who is listening? There are lots of tools available to monitor online comments and several of them are free.

Google Apps – monitor keywords and receiving streaming or batched reports

Technorati – one of the leading blogsearch engines

Jondange – Their Top of Mind (TOM) report tracks consumer sentiment across the Web

Trendrr – uses comparison graphing to show relationships and discover trends

Lexicon – searches Facebook walls for keywords and provides snapshots of chatter volume

Monitter – provide real-time monitoring of the Twittersphere

Tweetburner – lets you track clicks on short links on Twitter, providing hard numbers

Twendz – piggybacks on Twitter Search to monitor and provide user sentiment on real-time Tweetstream.

If you have some money to spend, there are more tools like TruCast, Radian6 and Cision, Techrigy and Collective Intellect. Website www.marketingprofs.com provides lots of good information about social media, too.