Got my self a 64 bit OWM Ultimate. Absolutely happy so far.
For both the retail and OEM version you are supposed to only have one installation, so no difference concerning that.
There is not support for the OEM version, no nice box and it only comes with one version either the 64 or the 32 version. Though the key is supposed to work with both.
But as the 64 bit version is anyway ok, I have not experienced anything with problems so far (was running a Vista 64 before), I would not see any reason the be concerned about that.
For both the retail and OEM version you are supposed to only have one installation, so no difference concerning that.
There is not support for the OEM version, no nice box and it only comes with one version either the 64 or the 32 version. Though the key is supposed to work with both.
But as the 64 bit version is anyway ok, I have not experienced anything with problems so far (was running a Vista 64 before), I would not see any reason the be concerned about that.