Adventism has historically condemned the use of wine as a beverage. It has not allowed it – period.
There is a lot of biblical evidence that this is an extreme stance, and that wine is acceptable. The biblical prohibition is not against wine, but against the excessive use of wine.
Is Adventism changing? In the Adventist Review [Internet Archive here], there is an article entitled The search for a “Thou shalt not” [Internet Archive here] – by Angel Manuel Rodriguez of the Biblical Research Institute of the General Conference.
He admits that the Bible is not entirely clear on the subject, and admits that there are verses that are problematic for the Adventist view. He still endorses the Adventist view that wine is harmful, and that abstinence is a better way. Few will deny that there is potential harm, and there is nothing wrong with abstinence. And yes, the Bible does use strong language against the abuse of wine. But the Bible does allow for its use.