Seems like a good car overall, but do a search on the "nissan altima intake manifold gasket".
Many people have experienced this same problem on this particular model; some have noted the same in their reviews here.
A required $600 fix mars an otherwise decent vehicle.
The engine is more powerful than other 4-cyl's I've driven, but you pay for it in gas mileage.
I suggest the company act responsibly and issue a recall, but I do understand that it's just a business tradeoff: it's better for a car company to ignore the bad publicity from unreliable vehicles until it becomes more cost effective to issue a recall and salvage their reputation.
Honda was more responsible to me in this regard.
I doubt I'll ever buy Nissan again.