Yes, there has been speculation that the face of Jesus that we see depicted in art is not how Jesus actually looked.
However, while "The Real Face of Jesus" is based on educated guesses, they are still that: guesses.
Historic artistic depictions of Jesus didn't really come around until a few centuries after his death. Obviously, the artists at that time couldn't have known Jesus personally, nor have heard about a detailed description of him handed down. Clearly, they based their perceptions of Jesus on speculation.
However, there are people who have (or claim to, at least) seen Jesus personally.
The vast majority of Christians accept that Jesus is alive and well, and that he is divine. As such, appearing to modern-day people here on Earth is not outside of the realm of possibility. No one who has ever claimed to see Jesus has ever discounted the traditional rendition of him that much.
One of the most amazing stories of a first-hand witness is that of Akiane. What's most amazing isn't just that she witnessed Jesus, but that she is also a divinely gifted artist, who undertook the task of painting the image of Jesus that she saw. This is Akiane's vision of Jesus. (If that ever breaks, just do an image search for "Akiane Jesus".)
Furthermore, this depiction of Jesus was confirmed by an unrelated boy, who also claims to have seen Jesus.
No one can claim to know what Jesus looked like unless they have actually seen him. The vast majority of artists have not seen Jesus. Therefore, we can safely presume that the vast majority of artistic renditions of him are simply guesses.
This includes--and especially applies to--the "The Real Face of Jesus".
Personally, I'm sticking with the depiction of the artist who actually saw Jesus that was confirmed by someone who is an independent witness.