The new firmware will be available to current iPhone owners if that is what you mean. As to the release, we will have to wait until tomorrow to hopefully find out.
You can get the latest update for the phone through iTunes.
Yes, the firmware 2.0 update will be available to the current generation iPhone. When? No one knows. I honestly wouldn't be surprised if it's on the 3G iPhone right away and "available" for the current generation later in the month. Another thing we don't know is whether the 2.0 firmware will have special 3G features that won't be available in the non-3G firmware.