My only concern with "growinold"'s comments is the one about anonymity.

While many of us who are "retired" may be less concerned with this, those who are still employed by IBM (and who will have most use for such a forum and who will have the most valuable information to contribute) will value anonymity highly. If they have to disclose personal information, then this will discourage many from joining and this is the last thing we would want to do.

It would be naive to suggest that such a list of real names would never be disclosed (the revelations about the extent of spying and the co-operation between technology companies and the NSA as disclosed by Edward Snowden should have put paid to any such optimism). The hosting site may be bought by IBM or have a agreement to share information with IBM, for example.

I do understand the need to validate those registering for the site (at least in order to post on it - I can't see the need for people to register just to view) and hope there is an acceptable alternative. I could go on and on about the erosion of free speech in the western world - but that is another subject (and if this also concerns you - then you could do worse than supporting http://www.libelreform.org/ and http://www.senseaboutscience.org/pages/keep-libel-laws-out-of-science.html)