What is an acceptable level of brain enhancement in social or work situations today? A strong cup of Starbucks? A Red Bull? A dose of Ginko Biloba? 54mg of Concerta? The current state of debate would suggest that the line for the average person on the street (ie, someone not diagnosed with a condition such as ADHD), the line is beginning to move from standard of over-the-counter traditional stimulants such as coffee, herbal supplements or sugary drinks to what one researcher calls cosmetic neurology. This is roughly defined as using heavier pharmaceuticals and higher dose supplements to attain states the brain cannot get to on its own: hyper-focused, able to stay on task for long periods under duress.
The issue specifically in question in a recent issue of Nature was the discussion by two academics of their colleagues' use of such drugs to further their working capacities. It is only controversial because use by academics themselves has been called out in public, while behind the scenes statistics mount daily about high school and college students' use of friends' prescriptions to cram for exams and otherwise extend study ability. Like alcohol, this use of so-called "smart drugs" is also finding its way into social and other professional situations, but instead of a drink to wind down after work, they are being used to enhance personality and performance in more important situations such as job interviews, presentations and such.
One analog to watch is the advance in enhancement in athletics. In the past decade, the line of acceptable assistance has moved from a good breakfast and some Gatorade to running with shorts interlaced by supportive bands of material that assist in muscle retraction for sprinters, as featured in the Adidas Techfit line of products. Today, no one complains about athletes wearing assistive clothing. So, after society moves beyond a few high profile "test cases" mulling the ethics of dosing the brain with smart drugs before a critical event (performing surgery, delivering the State of the Union address), we will all move on to find our breakfast cereal or morning juice will contain a hint of DMAE in a few years.
Of course, we could just stick to drinking tap water.