We are in the process of choosing a new roof for our home. We have a one story house that presently has a wood shake home. If your existing roof is wood shakes, I would recommend another product. Wood shake roofs are very expensive and also a serious fire hazard. My suggestion would be to remove the wood shakes, install plywood sheathing and install a dimensional asphalt shingle roof.
Dimensional roofs are really neat.
The shingles can be created to look like virtually any type of natural roofing material ,wood shake, slate, even clay tile. For person who asked last week about Feng Shui in new construction, I have two links that will help you. Both have contact links for designers. It's definitely a job that you'll need to do yourself, but one that's well worth the effort. By sealing the grout it will stay cleaner longer, it will be much easier to care for.