I just emailed a new client who asked the same question and answered that yes I did think so, and that I joined the BBB myself last year for the first time since i closed by brick and mortar computer store in 2002. I joined because thought (and still do) that it was a relevant and respected trust signal not just to Google, but to end users and anyone looking at my sites also, so I shelled out the $700+ annual fee.
That said,the BBB does sort of have an expensive racket going, don't they?