Water pump was replaced in 2006 because the noise I was hearing sounded like the bearing in the water pump was going bad. Recently, but for months, the coolant in the recovery tank had to be replenished periodically. I replaced the radiator hose on the passenger side (Jul 31, 2012), sometimes called the lower radiator hose, because there was liquid on the hose - and it is 9 years old. The tiny spots of liquid continued, so I replaced the water pump a couple of days ago (Aug 13, 2012). With expansion / contraction of liquid coolant, it takes a while for the coolant to reach a constant level. Hopefully, the water pump was the problem, not the radiator. However, the bearing didn't seem bad, so maybe it was just the gasket leaking. There have been NO puddles under the car, but who wants to sit on the side of the road waiting for a tow truck.
UPDATE: Two months later (Oct 8, 2012), the coolant began leaking again, and this time it was leaking onto the driveway. Naturally, the coolant level in the reservoir kept going down. The diagnosis was that the intake manifold gasket was leaking coolant. Upper gasket, plenum gasket, coolant and oil & filter were all replaced (although I had replaced oil & filter just 300 miles earlier). 79,600 miles. At the same time, a left front hub and left tie rod (outer) were replaced. Labor was about $530 at $100/hour.
Overflow bottle was empty, pooling of coolant found in garage under car. The water pump was bad, had mechanic replace. Mechanic also replaced serpentine belt which was cracked. 3weeks later, today, now car in shop for ac compresser clutch failure. Noise heard at idle. Metal shavings can be seen beneath ac compressor clutch. Mechanic stated it is less expensive to replace whole unit instead of just clutch attachment, due to labor.