I switched from a very reliable and efficient S-10 after 15 years of daily use. Almost 2000 miles on the Mazda3 so time enough to review: really good interior comfort (I'm 6'2), great acceleration with the 2.3 L engine from a stop (though not quite as eager when merging onto the highway), and stylish, masculine exterior. I like that this is close to the end of the production cycle so the bugs are mostly (hopefully) worked out -- learned this lesson from the '93 S-10. This is really 2004's best car with fewer trouble spots and 2008 technology and safety equipment. Best of all, I have averaged a better than expected 32 mpg with roughly 70% highway driving and heavy A/C use.
iPod connection, better than expected fuel economy for the 2.3 L, great looks, copper red mica color, and passenger side fuel door (really helps at the one-way-in one-way-out places where cars line up on the right side of the pump and leave the left side open)
Foot rest for left foot, visor extenders, gas cap holder, trunk release on key fob, option for gray interior color, and make the trip computer standard since the thing is already there but just locked on lower models.