As a guidebook, it's not bad. It doesn't list a ridiculous amount of travel resources--they keep their recommendations short, sweet, and to the point. That being said, they do tend to highly recommend the popular tourist spots first, then the lesser-known places. One of the benefits of Lonely Planet's competitor Rick Steves is that the latter doesn't pander as much as typical tourist resources do. He tells you exactly what's what, regardless of whether that's what the destination wants you to think about their fill-in-the-blank.
Still, I think the brief historical background included in this book for each region and background information on each city and town was really helpful. Or would be helpful if I ever go to Romania. I also liked the blue highlight boxes that popped up every few pages. I got to learn about a lot of cool things.
Romania in particular is a bit of a tricky country to understand, geographically, since pieces of it have shifted around so much over the centuries--even in the last century! So I feel like Lonely Planet did a good job of clearing up a lot of that confusion. They were really hesitant to talk about Roma culture though…I found that fascinating considering how they are discriminated against by most Romanians and other Europeans.
I'm not saying this is the best guidebook ever--it's certainly a bit stiff and it lacks pretty pictures--but I think it's useful.