I'm a fan of Volvo. First of all, yes they're owned by Ford but all of their current models (except the new S40/V50) were designed and planned before Ford stepped in so the comment about the S60 looking nice thanks to Ford is flawed. Actually, the S60 was designed BEFORE the S80 but due to timing and money Volvo opted to build and market the S80 first, banking on making enough $$ on sales to afford to build the S60.
The new S40 is a nice compact, but personally I think it's waaaay overpriced and looks too much like a Honda Civic (from the rear). The S60 is now a good car for the money since they're selling it at good discount. The S80 without the turbo engine is also good value for your money, but the T6 model is too expensive for my taste, although you do get a lot of car for the money compared to the competition (one of two Volvo models that could be compared to BMW 7 series (the old one) and MB E-class. The other Volvo/BMW comparison would be X5 vs. XC90). However, there are certainly a lot of Japanese cars that are better value.
The R cars (S60 and V70) are really good value for your money and they're a lot of fun to drive. I'm not sure I believe in their longevity though, with that much boost in a 2.5l engine and the very advanced (and IMHO high maintenance) 4C chassis. Of the two cars, I have to admit I think the S60 is very good looking, but the V70 wins out due to the fact that this is a station wagon and it moves like a race car! The shock value is hard to beat.
Volvo's station wagons are in my opinion the best cars they make and the clear winners of all station wagons available. Granted, you don't need one unless you have a family, but if you do you can't go wrong with them. Across the board they're great drivers, with a little nod to the 2.5T since it has gobbles of torque so the power is there when you need it. The current T5 is a performance chaser, i.e. you need to whip the engine to get the reward. The 2005 model has apparently been reworked to deal with that so you'll have the torque AND the power where you need it.
The XC 70 is a bit of a hybrid, being a slightly raised station wagon. Its ground clearance is actually higher than a Ford Explorer, and on snow it's all you need. For serious off roading it will do more than you think, but it's not a real off roader.
The XC 90 is a very nice ride. It swallows the freeway miles while bathing you in comfort. And if you take it off road, as long as just one wheel has grip it will climb up most anything. It's no Range Rover, but it performs better than expected. The T6 is thirsty though, and the T5 is not powerful enough. That will be fixed in 2005 when a V8 powered version will become available.
Across the board I think Volvo's have one of the nicest and most comfortable seats out there, and coupled with safety and practicability they are really great vehicles.
As for the depreciation, some are worse than others. It also depends on where in the world you are. For instance, in SoCal the XC 70 and the XC 90 depreciate very little. The XC 70 is probably one of the best vehicles you could get in that regard.
Owning a Volvo is more expensive than owning a Toyota or Honda, both in purchase price and maintenance, but the reward is a safe vehicle that if maintained well will last you a long time. Volvos are no BMWs or MBs, neither are they Acuras or Lexuses, so a comparison with these wouldn't be fair. However, compared to VW and Audi I think they fend for themselves pretty well. And as I said, as far as station wagons go, they're one big step ahead of the competition.