I've been using carPCs since about 2001 when I bought my first laptop and immediately started buying NatGeo TOPO states. I'm gonna be getting a copy of the OJ article to see what it says, but here's my take:
On my touchscreen netbook (lenovo S10-3t) I use the following software. Sometimes all at once, sometimes not (I've had no problem running 2-3 mapping programs at once on my netbook, they aren't very resource-intensive)...
Bluetooth GPS BU-359
XPort GPS software, it makes the GPS signals available to more than one program at a time.
ON THE ROAD
Microsoft Streets and Trips...I love this for basic routing, and tinkering. Probably because I have every year of it for the past 7 years
Plus, I have loaded in every campground and brewpub in Washington & Oregon, so it's easy to find the nearest place to get beer for my camping trips
Delorme Street Atlas 2009 - ok software, it has the phonebook which is mostly up-to-date. Works ok for tracking while you are driving.
Garmin Mobile PC - Just started in on this. I think this works well for the navigationally-challenged, but I find this (and most other GPS units) annoying. I'm a 'look at a map' type, so your mileage may vary. I do love the gas prices feature if you are networked.
OFF THE ROAD
NatGeo TOPO - Best if you are old-school topo-map type of guy. Lots of detail. Real-time tracking works ok. I use this most because i can load maps into my Windows Mobile phone and use them real-time outside the car. Overall the best bet if you can handle the cost (get backroads explorer and you get 100k maps for the whole US). Easy to d/l waypoints to a GPS if I want to use that (mostly I use my winmo phone unless I need sirfIII).
Delorme TOPO - Close 2nd. I run both at the same time. I like the delorme better for just driving around off-road, and it is definitely more up-to-date.
If I had only $100 to spend, I'd get GPS+Delorme TOPO. It has up-to-date maps, decent topo features, and is a good overall value for your money.
If you have the money, get them all - they have their strengths/weaknesses and i find myself using different software for all the different things I do.
As a note: There is OziExplorer and Overland Navigator...I haven't had a chance to mess with them, but I hear they are great software packages...
Ideally, I'd have them all available, and run