I don't think this is what won over the geeks. It is more of a mutual relationship -- IBM needed to take on Microsoft, and Linux was the easiest way to do that. So, IBM gives the open source developer time, money, and their patent portfolio, and IBM can compete better with Microsoft.
The Thinkpads are also mighty fine computers. (I know it's not IBM anymore, but times have changed...)
Sure. I didn't mean to imply that said campaign was the crux of the winning-over, but it was part of IBM's strategy to become cool again in the techie world. Just embracing Linux as a business strategy wouldn't have done it -- a lot of vendors have done that and remained uncool -- but what IBM pulled off was a strategic shift while bringing in the hacker community at the same time, which is pretty impressive.
The Thinkpads are also mighty fine computers. (I know it's not IBM anymore, but times have changed...)