Part of me sees the argument more with LOTR than with The Hobbit... The Hobbit was, for all intents and purposes, LOTR Lite... It was intended to be an easier read, an easier story... Liberties are cooler to me then with The Hobbit. LOTR didn't bother me with what changes were made though... As a different media, you almost had to accept certain changes. Films that acted out the books line-for-line would've been more than the 3 epics that we got.
Either way, I'm a huge Tolkien fan, and I'm excited to see a new film in the genre... There's only so much they can do, and this is pretty much the last gasp unfortunately. The Silmarillion would never translate to a series of movies. The Hobbit may translate far better than LOTR even did.