I had a bit of an epiphany this last weekend, as I was laying plans for next cyclocross season, and realised how effortlessly in my mind I had made the commitment to train 15 hours per week for the next 8 months, buy a new race bike (2k+), buy three new wheelsets (2k+) and enter the National Trophy Series in addition to the London League, with all the time and travel commitments that entails. Yeah, that feels fairly serious.
Not quite as bad as that, but getting close.
I was serious about MTB'ing in my teens - up to and including racing up to a national level sometimes. Then uni/alcohol/girls came along and exercise got boring. Fast forward a number of years, lost some weight, got a new job and my employer offered C2W. I decided on getting a road bike as I'd fancied trying one out for a while. Endomondo shows that between getting the bike in August last year and then end of my first sportive at the start of October, I put in over 800 miles. That's going from my first, near-vomit-inducing 26 miles, to putting in a sub 4h 100km effort. I even lost the best part of 2 stone along the way.
Since then, I've made plans to take part in two 100 mile sportives a week apart in June this year. They're at opposite ends of the country, but I genuinely thought nothing of planning the week inbetween to ride from one to the other, to make it up to about 600 miles in 7 days. I've joined BC, obtained my provisional race licence, with the aim that I'll take my new-found fitness and try out racing towards the end of the year.
Since the start of 2012, I've stopped drinking nearly all alcohol, cut carbs and started a training plan. I've started reading about (and partially understood) terms like ATL, CTL, TRIMP and TSS. I've lost another half-stone nearly. I get up at 5:30 most weekday mornings to ensure that I can get an hour on the turbo before I go to work. If I miss a session I get annoyed at myself for being lazy. I get frustrated when I don't know the best way to train, or if I don't get the results I want, or because I can't afford a power meter. I've logged ~150 miles (indoor and out) since the 2nd of January and I don't think it's enough.
In short... I got serious about cycling quite a while back. Now I'd say that I'm borderline obsessive!