If you've been holding off for the usual fear of having none of your progress matter, you can take heart that no further progress will be wiped between now and the conclusion of testing. Whether or not this will be the final test phase or an interim step is not announced. But test away, knowing that the only difference between now and launch will be the addition of the cash shop. And presumably some bugfixes along the way.
[Source: OGPlanet press release]