There are Gay Presbyterian pastors, just like there are gay Methodists, Catholics, Disciples, and Baptists. In many cases it's not allowable to reveal oneself, but I guarantee you that they're there. Indeed, there are likely gays among the pastors of Pentecostal and Bible churches, but they stay in the closet.
The news is that the Presbyterian Church (USA) General Assembly, meeting in San Jose, California, has voted to allow the ordination of gays. But this is only the first step, now a majority of regional Presbyteries must agree -- which might not be possible (yet). As the LA Times article quotes a delegate -- this is increasingly a generational issue. If it's generational, then it's only a matter of time. The Presbyterians will lose churches, but likely not that many.
But, again, it's a matter of time.