And the 10 downsides
1 - leaking data - a data breach can cost large fines and loss of reputation. Some social networking sites have tortuous privacy settings that are continually changing. You talk of collaboration, but what if that is between two people dealing with sensitive information e.g. a person requiring care at home?
2 - malware - social networking is yet another entry point for malware. Made worse if you use HTTPS because that then bypasses UTM and other perimeter protection methods.
3 - reputation - feeling annoyed - well venting your frustrations immediately to social media is not going to enhance the reputation of you or your employer
4 - legal - social media is publishing, and thus liable to the laws of libel. Journalists are (or should be grounded) in at least the basic law around this; your average Facebook user is not.
5 - security - the more that is posted publicly, the more data can be joined up and build a picture of an organisation - thus aiding in social engineering attacks
... add 5 more of your own
I hear all the arguments about it being great for publicity, but unless social media is totally different, consider the adage that applied up to now - "one dissatisified person tells 10 others; a happy person tells one". Thus negative information grows 10x faster and propagates 10x wider than positive information. Certainly when I look at comments on news articles, negative comments usually outweigh the positive comments significantly except for the occasional good news story (a rarity anyway).
There are some business for which utilising social media to its fullest extent is a business benefit, but for many others, the risks outweigh the benefits.
Back in the mid 1980s (circa 1986) I experimented with using a BBS to post common responses to technical support issues. (BBS were probably the first social media). However, in less than a month, it became clear that a limited number of individuals were using it to post personal attacks and so it was shut down.
Social media is not the great panacea that will make all businesses greater
