I found very interesting post on Tom Barrett's "ICT in my Classroom" blog about how Twitter is used as an educational tool.

Tom's post also describes where Twitter is positioned among other communications tools. Twitter is not a synchronous or an asynchronous communication system. It is rather both at once depending how channel's followers use it.

He makes a nice metaphoric comparison between Twitter and a flowing torrent where people can just stand by it and observes the flow. Some prefers to jump into while others simply do not pay much attention to the  stream.

Personally I am amazed to see how many different ways Twitter is used today. There are, indeed, lots of individuals (you and me) but also some politicians (Clinton, Obama, UK Prime Minister), Public Services (LA fire department, AmCross), Airlines, News agencies, etc.. which are increasingly using it, but not necessarily to interact with others but to broadcast content or information.

Is any company using Twitter for internal use only ? 

London police launched on 25th of February a new advertising campaign. Posters and TV ads are urging Londoners to turn in people who might be taking pictures of CCTV cameras.

"Thousands of people take photos every day.

What if one of them seems odd ?

Terrorists use surveillance to help plan attacks, taking photos and making notes about security measures like the location of CCTV cameras.If you see someone doing that, we need to know.

Let experienced officers decide what action to take." 

Other posters target households:

"you see hundreds of houses every day. What if one has unusual activities and seems suspicious"

as well as mobile phone users :

"Thousands of people have mobiles. What if someone with several seems suspicious?"

What's going on in London ? Is the Metropolitan police not busy enough ? did they become completely paranoiac ? or do they need some budget increase ?

Where is this so famous British phlegm ?

As a response, many people have already redesigned the posters to point out the absurdity of them. Some samples are available on BoingBoing.

Saw yesterday night on TV. 

Last Saturday, during powerful storm Emma,  39 years-old Lufthansa pilot attempted to land his Airbus A320 with 131 passengers in Hamburg’s Fuhlsbüttel airport.

Facing winds up to 90 km/h at the moment of the landing,  the left wing grazed the runway for a moment, but the pilot was able to stabilise the aircraft and take off.

The plane landed safely 15 minutes later on its second attempt.

All passengers and crew were unharmed and the aircraft was only slightly damaged. After having its wing tip replaced the A320 was expected to be back in service on Monday. 

Well Done Captain !