If you attend IT management-focused events and communities, then you have probably come across former CIOs. After stepping down from their last senior IT job, they decided to take a sabbatical to write a book, rethink their career, study their options, become an interim/advisor/board member somewhere, form a consultancy, become a visiting professor...
While the strategies people adopt after leaving a job vary, one thing I have noticed is that many of these professionals seem to use their old jobs as some sort of walking stick: it is not about their ideas, what they are able to do, their current projects, or future vision: it is all about the past. And at times, they boast about roles where they were not even all that successful.
You also see many senior IT folk clinging on to their old job titles for as long as they can, both online and offline. Perhaps to make as many connections as possible on LinkedIn since they are out of a job? But isn't that cheating a bit?
I have seen an IT executive speaking at a conference in London last year under the title of "former CIO at XYZ Industries". Sure, it's all fine to talk about a specific theme based on practical experience, but answer audience questions about what might happen in terms of the company's current strategy? The person in question was doing just that - not cool at all.
While it is perfectly normal to use your reputation to build connections and raise your profile, there seems to be a fine line between those who behave as experienced professionals who are respected by their peers and those who are perceived in the market as just another "has-been".