I just took the bus today after cycling in for the first time yesterday - bum needed to recover!
Door to seat, the bus takes me about 45 mins - 10 minutes walk to bus stop/waiting, half an hour on the bus and 5 minutes getting into office, finding desk etc.
Cycling yesterday, despite being horrendously unfit, took me 25 mins from door to locking bike up. Having forgotten my pass I couldn't get into the office from the car park so had to go back round and in the front door to sign in, adding a few minutes, then took 10-15 mins having a shower and change so overall I'd say there was no difference timewise.
Riding back yesterday though, with more uphill work, only took 22 mins so think I can probably get into work in about 20 without needing too many fitness gains first. Remembering my pass should then save another 5, making it 35 minutes door to desk - a 10 min saving.
Add that to the fact that when I cycle I wont have my face in someone's armpit, and get a seat (of sorts), then I think the bike will be getting a whole lot more use in the near future! Just need to find a way to make my rear able to withstand it better...
Not sure about the cost savings to be honest, by cycling I save £3 per day on bus tickets but then need to eat more; based on bus tickets alone it'll take about 130 days of riding to break even on the bike alone, before taking into account locks, mudguards, pannier rack&bag, clothing, tyres, insurance etc. Though I guess if you amortise it over 3 years (as HMRC seem to think is a reasonable useable life) then I would be pretty well up!
Nonetheless, I don't feel that doing a costing analysis on cycling vs public transport is a worthwhile exercise - there's some benefits from cycling that you just can't really quantify!