So far we have formal announcements that 2008 will be their last season from:
Graeme Hick, Darren Gough, Kevin Dean and Iain Sutcliffe. Mushtaq Ahmed and Jason Gillespie of the overseas-players as well. And I'd be surprised if we see Deon Kruis again either. Not sure whether it's the last we've seen of Grant Flower, Jason Gallian, Alex Tudor, David Hemp, Craig Spearman, Carl Greenidge, Dominic Cork, Lance Klusener, Matthew Nicholson or Rana Naved-ul-Hasan, but in each's case I hope it might be, for reasons varying from "never any good" to "his time has come" to "he's an ICL player who is very possibly doing his county more harm than good". But with Shaun Udal and Ian Salisbury being tempted out of retirement only to make their retired-from counties regret not trying such a thing themselves, don't count your chickens.
Confirmed overseas-players for 2009:
Derbyshire: Chris Rogers
Glamorgan: Herschelle Gibbs
Hampshire: Imran Tahir
Know for certain Yorkshire are currently still trying to get Morne Morkel, and presume Somerset are keeping Justin Langer as he hasn't announced his retirement; I guess Essex will be making every effort to re-sign Danish Kaneria, and likewise Lancashire Brad Hodge.
I also presume Middlesex, Warwickshire and Worcestershire will be looking for new ones. Likewise, Leicestershire and Northamptonshire simply don't have just 1 overseas-player so it barely matters who is officially registered as such.
What we do know is that UCCE-vs-county games will soon be no more. And a damn good thing that is too IMO.