I’ve been using Twitter in earnest for a couple of weeks now, and I have to say it’s genuinely surprised me. At first I was sceptical. What possible value can you squeeze into a 140 character post? Plenty, as it turns out.

But the real value of twitter (and I guess other micro-blogging/short message broadcast services like Jaiku and Pownce) isn’t about individual messages — it’s about the cumulative stream of messages: what that reveals about you and the people you’re connected with. I love it.

In the short time I’ve been using Twitter I’ve realised that it really can add tremendous value in lots of ways:

Some of twitters strengths

• you to feel more connected and in touch with the people around you
• it helps strengthen your relationships with the people you already know
• it’s a great way to hook up with like-minded people you don’t know
• you can follow thought-leaders and innovators in your field, see what’s on their minds, and gain tremendous insight from that
• it puts your finger on the beating pulse of your industry — if it’s happening people are talking about it on twitter, and linking to valuable resources on the web
• it’s a great way to harness groundswell to promote new products and services through social media (as witnessed recently with @patphelans remarkable Twitterfone launch) — see Pat’s Twitterfone launch summary on his blog.

I’m sure there are plenty more. Of course it’s also a big distraction and potential time waster… but I’m working on that .

But now the subject of Twitter Spam has reared its head, with the publication of a new Twitter Black List.

Which begs the question, is spam really going to be a problem on a service that’s fundamentally based around opt-in? You only see the tweets of people you choose to follow, and you can opt back out again at any time if they start posting lots of spammy tweets. From my admittedly limited experience you don’t need a blacklist to spot potential twitter spammers — you just need a soupcon of common sense.

When someone on twitter follows you, resist the guilt reflex to follow them back, and check their profile and their twitter-stream to see if they have anything interesting to say. If they do, great, if not… or if you see a lot of spammy links, don’t follow them… simple.

Where’s the problem?

Danny Sullivan posted a terrific summary of the twitter spam issue over on his Daggle blog recently. It’s definitely worth a read.

One thing in Danny’s summary — about Twitter’s @replies confused me a bit though.

Danny says:

@replies. By default, you will only see messages from people who call you out using your name (like @dannysullivan) if you are following them. This means you’re initially safe from unwanted messages — no one you don’t know can show up in your Twitter stream. But some change the default to see @replies from anyone. I do — and it’s a great way to meet new people you aren’t following. If they say something interesting, catch my attention somehow — I’m like great! A new person to follow. But it also means potentially, people you don’t know can get into your Twitter replies tab or if you use a tool like Twhirl (love it, recommend it!), then they’re potentially even more in your face. Yeah, there’s a “spam” potential there, and hopefully it won’t grow. If someone is abusive, you can block them individually. See this on Twitter for more about @replies.

Now, I interpret the Twitter Support page on @replies a little differently from Danny. I think the @reply settings on your Twitter profile relate to @replies SENT TO OTHER PEOPLE by the people you follow. The options are:

• You receive @replies sent from the people you follow only if they’re sent to other people you also follow. (this is the twitter default setting)
• You receive @replies sent from the people you follow to any user regardless of whether you follow them or not. (this is my preferred setting and a great way to find new and interesting people connected to the people you’re already following)
• You don’t receive any @replies sent by the people you follow to anyone other than yourself.

You will ALWAYS receive @replies directed at your particular username from anybody (i.e anyone who types in @yourusername), regardless of your settings and regardless of whether you follow them or not. Your Twitter @reply settings will dictate whether you see replies sent from the people you follow to other people… if you follow that!

To test this I just created a new user (not following anybody and not followed by anybody) and sent an @reply to my main account. It got through perfectly, as did the reply I sent back in return.

So — is the fact that ANYBODY can @reply anybody else, without the “Follow” opt in a good thing, or a potential loophole that spammers could exploit in the future… comments please!