Swiss are refitting both C & F from April 2009 onwards, with New York the first route to be completed. Details are already discussed maybe here and for sure in the M&M forum, plus a Link. Having never flown either I can't help with the which is better question. What I do feel compelled to point out though is that if the final destination is MAN be aware that LHR-MAN on bmi is Y only, and although I might be wrong here I think if you don't have status there's no lounge access on an award ticket. Where as the C service from ZRH-MAN is very good by intra-european standards and you'd be welcome to use the Swiss lounge.