Why it pays to be social

I suppose this is a bit of an advert for what twitter can offer for learners experiences, as I currently find myself in the situation where I'm looking to state a case for our departmental account adding value.
Context
My S4 classes have been looking at land use in towns & cities, primarily through a streetview tour of the mean and mild streets of Glasgow (I may have shown some bias in the choice of location). I wanted to assess the class understanding of the expected pattern of land use through real life examples. I needed to source these quickly while the topic was 'hot' and also wanted to extend thinking skills by using some examples which didn't exactly fit the norm. Enter the networks...
Social Services
I put out a tweet, more in hope than expectation, asking for any people in my network, if they had time, to share in 140 characters a little clue about their own urban environment - simple things such as the type of houses, services, transport, recreational space immediately surrounding them. My twitter timeline is public, but I also sought some help through good friends on Facebook, who had a little more room to express themselves. The response from my social network was quite staggering and in a very short space of time I had a rich source of lesson material.
Where am I?
I decided to keep the lesson simple for now with a possible follow up. I provided a blank urban model with clearly defined zones; the central district, inner town/city, suburbs and the rural/urban fringe. The students worked in pairs to put my friends names in the correct urban land use zone. For example, 'Andy' stayed next to a golf course, a lough and a convenience store but in a mostly residential area. Students quickly decided he was in the suburbs. This was correct, as Andy stays a few miles out of Belfast. Others were harder. For instance, 'Max' stayed in a pretty tree lined area, but also talked about the Southern mainline and the 5 takeaway shops on his doorstep. This kept the class occupied for most of the period but inevitably, students being full of doubt for my good intentions, they wanted proof that these were indeed real people. Which brings me to the potential follow up. I aim to put some students work out via posterous to let those who contributed see where their clue put them, but would also like some element of personal response to a selected few from the students.
Conclusions
This lesson was spur of the moment, quick to source but now sustainable as I have a permanent resource from it. I have been able to share the resource with the department, giving others the opportunity to use, adapt, create from it. My students interest was sufficiently sparked by the characters that they effectively engaged with both the activity and the learning intentions. The exercise required students to be critical thinkers and make decisions where the result wasn't always obvious and justify it. Finally, the lesson was created by drawing on a wide population sample giving a relevance and reality to the work that the class have been doing. Once again, a huge thank you to all who participated, without you, the lesson wouldn't have existed and, I suspect, the topic that bit more distant from the learners.