When there is an official ruling, it may come out something along the lines of this:
Nelyo 05-29-08, 12:33 PM
"Say I have a Fighter using a Longsword + Shield combo, and he has the Fighter Weapon Talent giving +1 to attack rolls with one-handed weapons. If I drop my shield and use my Longsword two-handed, do I still get +1 to attack rolls from my Fighter Weapon Talent? If I'm using a feat or power that gains extra benefits for wielding a two-handed weapon (like Reaving Strike or Power Attack) do I get those bonuses? Basically, when you wield a versatile one-handed weapon two-handed, for what purposes is it still considered a one-handed weapon, and for what purposes is it considered a two-handed weapon?"
WotC Mearls 05-29-08, 07:33 PM
"This is not an official answer, but let me give some insight into how versatile is intended to work.
As a rule of thumb when using a versatile weapon, default to giving the player the most beneficial reading of a rule or situation regarding one or two handed use.
So, the fighter would still get his weapon talent, and he could also gain the benefits of reaping strike.
Versatile is intended to let you have your cake and eat it too."