We took a look at this Hitachi plasma with eCoustics a few weeks back, which was not a favorable one.

The guys over at Ultimate AV give this plasma a bit more credibility:

Pros
Stable, detailed, richly colored picture
Full feature set
Excellent remote

Cons
Mediocre black level
Inordinately high red push

Conclusion
There’s a lot to admire on this plasma. The feature set is complete, the price is good. The black level is not among the best I have seen, which is the only thing that keeps me from offering a high recommendation.

I still think you’ll get more bang for your buck with a Panasonic. But that’s just me.
Ultimate AV: Hitachi 42HDT52 Plasma Television – via HD Blog