Sarah has kindly volunteered to blog it for me, which could offer an different perspective, as she's never even been to London. However, when I last e-mailed her, she was under the impression I walking on Sunday, not tomorrow. A couple of other people have kindly expressed interest in doing it, but not at such short notice.
Go check out Sarah tomorrow morning. Even if she's not blogging the walk, she's bound to be providing good content - she usually is.