This story is still rumbling on, but there still does not appear to be any greater clarity about why those with apparently good credit records are having their Egg cards taken away. A lot of the press coverage implies that the cynical theory - that they are being booted because they make the company little money - is correct. I can't find any factual support for this suggestion and all the comments in support seem pretty vague or unattributed. In contrast in a number of places Egg specifically denied the claim.
Strange one. Whatever the real story it has been a bit of a PR disaster for Egg, though if they are only annoying people they want to dump as customers in any case I suppose it won't matter. There are also reports that other companies might follow Egg's lead. It does all point to it getting harder to borrow if you are the lower end of the market.