Blizzard is cracking down on group finder advertising. The move is directed at groups forming to offer boosts that are "often used as a cover for real-money sales, particularly given that in-game gold cannot be transferred cross-realm" the post reads. The policy to remove those types of groups is in force as of today, July 2nd and a new reporting option for "advertising" will be added with the v8.0 pre-patch update in a week or two.
[W]e will no longer allow any advertisements in the Group Finder for in-game services such as carries or boosts, including those being offered in exchange for in-game gold. The Group Finder is intended for -- as the name suggests -- finding groups, and these advertisements make it difficult to find active groups that are currently being formed.
Note that this does not change our policy on selling things such as raid carries for in-game gold. Those are still allowed, but should be advertised through realm-specific methods such as trade chat.
For those of you who love to see fun and interesting ways players choose to take on WoW, you may be interested in an intrepid team of three (Paladin, Hunter & Warlock) that managed to take down Argus the Unmaker, the final boss in the Antorus raid.