Keynote monitored 2000 prospective credit card customers as they interacted with leading credit card Web sites and found that Discover, followed by American Express and Chase, provide the best overall online experience for prospective clients.

More than half (52%) of prospective credit card customers consider online account management an essential component of credit card services, says Keynote, with only account fees and interest rates considered more important as a selection factor.

Discover was considered the easiest credit card to apply for online - and the easiest company to deal with, accorrding to two-thirds (71%) of online consumers.

American Express was considered the "high value" and most "trustworthy" brand by online consumers, and made exploring online services easy for prospective card customers. The site also ranked highest in satisfaction in the area of online services offered.

The Chase site performed well in the area of customer support. Chase was also one of the companies - along with American Express and Citi - that performed best in attracting new customers.

Around 30% of prospective customers visiting the Chase, Citi and American Express sites indicated they were "very likely" or "extremley likely" to sign up for a credit card account with those companies.

Bonny Brown, director of research and public services at Keynote Systems, says although the online channel has not traditionally been where consumers apply for cards, credit card sites and online services do have a major impact on consumer decisions.

"The impact of card sites on consumer decisions and behavior is steadily increasing, and card companies need to sit up and take notice," adds Brown.

The study also found that HSBC, Providian and Wells Fargo Web sites had the best reliability, indicating those sites were highly available and experienced little or no downtime.

HSBC and Providian were also best in terms of site responsiveness, an indication of how fast the sites were in down loading pages and conducting transactions. Chase was also a leader in terms of site responsiveness.

Keynote says the industry seems to be gearing its business primarily toward broadband users, and service for high-speed users was excellent with average page downloads of just 1.7 seconds, with MBNA and Wells Fargo loading in under one second. However, performance for dial-up users was just "mediocre" with page downloads averaging almost 30 seconds. The slowest performance for dial-up users was during the account application process.