Just did test drive on Volvo S40 2 weeks ago. Nice car, but engine not so powerful. Volvo is known as the most safety car maker, however the IIHS's crash rating does not agree that. Most of the 2010 cars are doing very well in front impact, but not in SIDE IMPACT. There are a lot of videos on youtube about side impact, you should seriously consider a real safety car.
I finally bought an Acura TSX (it's not the same Accord) because TSX gets all the best crash rating (better than S40), and also received the highest rating in EURO NCAP (European's crash test). All TSX is made in Japan, Accord is made in US. TSX is heavier than Accord, but TSX's engine (4 cycl) is 201hp, Accord is only 170hp. I test-drove both Accord and TSX, totally different handling feeling, they look similar inside, but they are just not the same car. BTW, TSX is actually smaller than Accord.
Volvo S40, 5 cycl engine, but not so responsive. Audi A4 has much better feeling than S40. I think Audi A4 has similar handling like TSX. All S40, A4 and TSX has similar starting price, but TSX has all features built-in, but S40 and A4 needs to pay extra for the options. So, TSX is actually a better money worth choice.
My test-drive cars: Altima, Accord, S40, TSX, A4. I was going to test drive S80 and XC70, but I gave up, because I love the TSX too much.