There is a compelling argument that 1080p is unnecessary at 42". So compelling that Pioneer don't even bother making a 1080p 42" set, as they believe it's only really of use at 50"+. To tell the difference, you'd need to be sitting closer than 5'-6' away.
Probably the best 42" Plasmas are (as mentioned) the Pioneer 428XD or the Fujitsu 58 series - neither of which are 1080p, iirc. I'm probably going to go with price vs. performance and get a Panasonic TH42PH10 - as I don't want all the tuner, speakers and other guff - just the panel. And at £750 + ~£85 for an HDMI board, it's a bargain. And I can't justify the extra grand for a £1700 Pio 428XD
Well my old TV is a TH42PX60 1024x768 G9 Panny, and I would tend to agree that 1080p is not really required at 42inch at any sensible viewing distance. If it wasnt for the occasional purple snake, the G9 Pannys still offer exceptional picture quality, and even the 1024x768 G10 pannys honestly arnt much worse (if any) than the Pioneer, and a TH42PX70 is a lot cheaper, and still supports 1080p inputs for compatibility with HD-DVD/BluRay etc.

