Twitter

I don't think I would use Twitter. It doesn't appeal to me.
It might be useful for posting news and upcoming events for libraries/branches etc.

LibraryThing

I found this site very user-friendly. It wasn't difficult to navigate.
I think quite a few people would find this a useful site to keep track of books they have read, are reading or would like to read.
I think that I will use this site and would also recommend it to customers.

CPL 20

I don't think these sites will replace microsoft office etc. There will be people who will use them but a lot of other people will stick with the familiar sites.
Personally, I would not use any of these. If my life were busier - a lot of things happening to trace maybe - but my paper calendar works just fine.

It is good to see what is available and have a general understanding of what you can use.

cpl2.0 flickr and you tube

I found both sites very user friendly. I don't think I will use flickr but will definitely use you tube and have gone to this site in the past.