I lead a regular pickup group run for 25-man content. It is composed of multiple guilds. This has been successful for us since, we're all in smaller guilds. It would be helpful to be able to have a check box on each player's page that would bookmark them on a separate tab for Friends, alongside the Guild tab. This way, I could sort out my regulars without having to check each, one by one. We use wow-heroes every week to check gear.
Also, it would be nice to have the same option for guild pages. We have an alliance with Maelstrom. It would be nice to be able to have their tab next to my guild.