I typically ride from 200-300 miles per month, mostly from daily commuting (I cycle all-year-'round), but that spikes up to 500-600 miles during the summer months when I also drive my cycle-taxi (an Anthrotech recumbent trike pulling a 2-person rickshaw trailer) to cart around tourists to hotels and train stations plus weekend drunk local folks from place-to-place (can earn about $150-$200 USD in pocket money easily on Fridays and Saturdays).
Not sure about much weight-loss yet as I still seem to have sort of 'IT-belly' from 30 years of sitting in front of a computer - and it's doesn't want to go away. Probably because recumbent cycling doesn't really work out the abdominals as much as I imagined it would. But I know I'm fitter than 25 years ago, and with legs muscles beginning to look like those you'd see on the Tour-de-France riders.
Although after my recent ride from Denmark to the UK and back, I notice that all of my blue-jeans need a belt or suspenders to keep up!