One of my favorite ways of wasting time is watching You Tube. There are too many examples of new or untrained riders having a bad day on their bikes. Entertaining, yes, but very sad too.
Speed power and size of the bikes is a major contributor of injuries and deaths. Lack of situational awareness becomes a major issue.
As a returning rider in 2005 I bought a Vstrom 650. I admit it was a bigger bike than I needed to return to the streets on 2 wheels. I felt way out of my league and luckily never became a statistic. Rider training ironed out the most glaring bad habits and the bike became much more friendly and my confidence grew daily. I was wrong in thinking my previous riding years would carry me through with a new bike. Fortunately my Guardian Angel was working overtime to keep me safe.
Start small and work your way up. There is no shame in a small bike, just sheer amazement what a newer small bike is capable of without going the speed of sound. Lynda showed me what her GZ could do in many ways. We rode the twisties, toured across Canada and had a lot of fun. Lynda often said the GZ was a perfect start to her riding career.

I went the other way. My last bike was Suzuki VX800 - beautiful but extremely heavy beast at 600lb (see pics below). I got tired moving it in and out of garage, parking and turning it around. Decided to sell and bought GZ250. Its about half the weight and 90% of the fun. Good enough for me.

http://www.gz250bike.com/forum/pictu...&pictureid=374

http://www.gz250bike.com/forum/pictu...&pictureid=373

http://www.gz250bike.com/forum/pictu...&pictureid=372

I'll try to explain it....
Before riding, everyone must take a compulsary basic training course, and pass a theory test.

Age 16 or over - Do the above then ride a moped up to 50cc with a top speed of 45k/h (around 28mph) with L (learner) plates, or take a test so you can carry passengers.

Age 17 or over - Take a test to ride a bike up to 125cc (max power 11kw)
After 2 years you can apply for a test to ride a bike up to 35kw (46.6 bhp) up to 500cc, or a restricted version of a bigger model. If you are 19 or older you can take a direct test for the 500cc licence, then after 2 years take a test for an unrestricted licence

Age 21 or older - you can apply for an unrestricted licence by...
(1) If you have had a 500cc licence for over 2 years you can take a test
(2) If you haven't held a 500cc licence for 2 years, and are 24 or older, you can take a stiffer test (which must be on a high powered bike) to prove that you can handle it.

Complicated eh!

Complicated but smart. Too bad one can't track the number of injuries and deaths this program has prevented. While I am not a big fan of government regulations and interference in our lives, this program actually makes sense. It is certainly less painful than our "natural selection" way of weeding out the bad riders, if you understand my meaning.

My only problem with the approach is need to buy several progressively larger bikes. But otherwise I like it.

You consider that a problem? I consider it an excuse to buy another bike. (Yes, I am not ignoring the financial aspect of it).

You need to learn to walk before you can run. Develop your skills on a smaller bike which will make the transition to a larger bike much safer and a lot more fun.
As you graduate up to larger bikes you learn what you really want in the long run. As you upgrade you may find that 600cc's is the most you want on 2 wheels rather than just guessing 1,000 cc's will fill all your needs first time around.
Modern mid sized bikes are great. They will haul your butt all around the world with little effort. Save the added cost of a modern big bike and it's requirements for more gas, more expensive insurance, larger more costly tires.
Jumping on the big bike bandwagon will cost dearly if it is wrong for you and you take a loss getting rid of the monster in the driveway.