Me! I've been doing Boston's Summer Sings, where every Tuesday night we sing a major work after briefly practicing.
Masterworks Chorale - Summer Sings
So we're singing the Brahms German Requiem (my personal favorite), Verdi's Requiem (another favorite, what amazing solo parts), and Faure's Requiem (great and very easy to sing). Also, this year my choir performed Durufle's chant-like Requiem.
I've never sung Mozart's, but it may actually be my least favorite. I find there's not a lot of variety between the movements; it all sounds like itself. Wolfgang only wrote about half of it anyway. I've heard recordings of Berlioz's, which I remember being good.
Oddly enough, I love Britten, but I still haven't heard his War Requiem. I need to remedy that pronto!