With more and more people using the Internet to shop for a new car, Kia.com has pulled into the lead.

The site ranks highest among automotive manufacturer Web sites for usefulness in the search for a new vehicle, according to the J.D. Power and Associates 2008 Manufacturer Web Site Evaluation Study -- Wave 2.

The semi-annual study measures the usefulness of automotive manufacturer Web sites during the new-vehicle shopping process. New-vehicle shoppers evaluate Web sites in four key areas: appearance, speed, navigation and information/content.

Kia ranks highest with an index score of 872 on a 1,000-point scale -- marking a nine-point increase from the last wave of the study, which was released in January.

Closely following Kia in the rankings are Ford (871) and Mazda (870), with Ford performing particularly well in the appearance factor. Also performing significantly above the industry average are Honda, Jeep, Lincoln, Porsche, BMW, Cadillac and Subaru.

"Over the years, Kia has successfully satisfied shoppers with its straightforward, intuitive Web site by providing pages that load quickly and that are easy to navigate," said Arianne Walker, director of marketing/media research at J.D. Power and Associates.

"By focusing on these key aspects of the Web site experience, Kia has continually met the expectations of its customers. In fact, this marks the fourth time in 10 reporting waves that Kia has ranked highest."

On average, most manufacturer Web sites undergo a major redesign every two to three years. While redesigns can eventually lead to increased satisfaction, small updates to improve critical areas on a manufacturer Web site -- such as information and content and ease of navigation -- can also positively impact the customer experience in a more cost-effective manner.

In particular, Ford and Porsche have made frequent tweaks and updates to their sites, all leading to a steady increase in satisfaction scores during the past four years, without a major redesign.

"Ford and Porsche provide a great example of how targeted, consistent improvements to a site can really pay off," said Walker.

"With limited resources at many of the manufacturers and their advertising agencies, choosing to stick with a well-thought-out master design while consistently improving site content, framework and behind-the-scenes programming can prove not only more cost effective, but just as successful as a major site redesign in meeting the needs of shoppers."

The study also finds the following key patterns:

• Satisfaction with a manufacturer Web site tends to increase shopper visits to the dealership, as 75 percent of shoppers who give high ratings on a site are more likely to go to a dealership to test drive a vehicle.

• Overall satisfaction with manufacturer Web sites has increased to 849 -- eight points more than the previous wave of the study. In particular, satisfaction with loading speed has increased as manufacturer Web sites have employed a variety of techniques -- such as better navigation schemes, more aggressive caching, better page load order and pre-loading of content -- to offer rich content that loads quickly.