Mescon said he understands why Valve would want to make a DotA-inspired game, but told Joystiq that he was "surprised that [Valve have] decided to try to trademark the DotA name, because it goes against what [he] and others believe DotA means to the community." He suggested that by trademarking the name, Valve is attempting to take ownership of the name and "exercising control over its future." Mescon believes the "DotA name should remain the property of the community at-large, as it always has."
Despite these issues, Mescon said, "We are actually really interested to see what they can do with this genre because we are excited to see companies of Valve's caliber to enter the space that we've been working in for the last few years."
We contacted Valve for comment on this piece, but as the company has yet to officially announce the game, we'll just have to continue following this story as it develops.