This is great news, in my book. While I can anticipate some concerns that this might encourage elitism or similar, it's actually going the opposite direction. Lore's concern for situations where teams filter on invite is very valid, as if a system is not included people will find some way to exclude those they don't want.
It's perfectly fair for teams to want to bring players of a similar gear level to their own, and a cursory glance at oQueue will reveal that while some teams will want higher level gear, rating or achievements, there are plenty of groups that don't. It seems highly likely that users of the Blizzard group finder will experience the same variety.
One other thing I'd love to see copied across from oQueue to the Blizzard group finder is the possibility for group leaders to earn some kind of rating. Not awarded by their party, necessarily, as that's open to abuse, but oQueue self-awards leaders ranks for leading. One thing an LFM group-finder such as this needs is leaders, and this is a way to reward them for their additional effort.