I was skeptical initially.
The laptop has been dissected and scrutinized by multiple people with nothing suspect discovered.
On the other hand - which brand is safe ? Thinkpad has installed rootkits multiple times.
Until there's proof to the otherwise, I think it's worth withholding preconceived ideas.
In any case, everyone has their own level of comfort, and that's important.
Are you talking about the Superfish vulnerability? It's never affected the business class Thinkpad lines [1], but it has affected a lot of the other laptops that Lenovo has shipped.
Not the best idea security and privacy wise.