A rising Case-Shiller Housing Index reading points to a growing and healthy economy. Homeowners feel more secure and are more likely to spend on home remodeling, repairs, and other things they need or want. In addition, developers, builders, and the like are more likely to put money into the economy by building more houses for people to purchase.
Finally, the Case-Shiller Housing Index can be used as a proxy for how much money is circulating in the economy. Again, positive moves correlate with more spending, and more spending means more money circulating, and that's great for everyone.