As far as rewards go, each BG has a vendor where you can purchase exclusive items, depending on your reputation. The honor kills and points come pretty fast there too, and you can actaully level doing them by accepting a repeatable quest for each one. I made roughly 6k xp for my lvl 25 doing two WG instances. But that's not why I like it. The action is fun

The team work is what makes it great too. In Arathi Basin, the horde were stomping the Alliance's rear every time we went in. There was no Alliance coordination, they'd take a resource then run off leaving it unprotected. So, the 4 of us ( Daimania, Dovenwolf, Crelt, Larong) were on teamspeak and decided to hold the line at the stables. Everyone kept coming by telling us to "follow them!" but we ignored them, well, a "whatever you say "boss"!" could be heard from someone...hehe. We held those stables too (the only held resource for the alliance) and were cheered by many. Go Avians

We could easily make a 10 man CTF team in Warsong. I love getting into a hairy sitaution, seeing my health drop fast, and doing everything I can to make sure I take down atleast 1 SOB before I die from the multiple attacks. And just when you think you're dead, bam, it's your friends to the rescue. The adrenaline rush is a nice bonus too lol.