Pokémon was cool when I was 12, when Red and Blue were released. I am now 22.
The answer that can be drawn from this information: Pokemon was never cool (i repeat, never cool), since only the 12 year old who *thought* they were cool played it and, more importantly, *NOTHING* is ever cool a decade later.
Case in point: 90's Brit-pop sensation Oasis. The teenagers of today see that band as granddad music, while the teenagers of the 90's loved their 'music'.
Even if there are little pre-teen-emo-kids out there with a love for pokemon today, they are most definitely not the cool kids. Unless we adopt a relativist definition of cool, in which case the thread is purposeless. ;]