You will need to weigh the situation.

If it were my company, we have a Core Value of "Truth", and we have an expectation of open communication with each other and with our clients. Therefore, if it was me, by running this through our values it would be a no brainer to tell people not just what was going on with me personally but also the decision to sell the company.

The other stuff about it being good for them and they'll make out on the deal - you don't have any control over how they'll feel about it. They may feel cheated, betrayed, or they may feel ecstatic. You can't know, and it's not up to you to decide for them. However, you can give them the information so they can make the choice.

Or, if you are a company where communication is lacking, transparency is not a value, and you honestly don't care what they think, then don't bother.

(Since you said you're keen to tell them though, I'd go with your gut.)