When choosing an aid or service, title II entities are required to give primary consideration to the choice of aid or service requested by the person who has a communication disability. The state or local government must honor the person’s choice, unless it can demonstrate that another equally effective means of communication is available, or that the use of the means chosen would result in a fundamental alteration or in an undue burden (see limitations below). If the choice expressed by the person with a disability would result in an undue burden or a fundamental alteration, the public entity still has an obligation to provide an alternative aid or service that provides effective communication if one is available.
Accessibility on the web can mean a lot of things. But in general it means making websites as inclusive to as many users as possible. Accessibility is important for a diverse group of users including mobile users, people who rely on assistive technology to navigate the web, and even search engine robots. We handle accessibility of WordPress.com in two simple ways.
The pressure is mounting to implement technology that more directly connects with residents, but balancing the shift to enable all citizens – including the approximately 19 percent with disabilities – can seem insurmountable. Beyond ensuring your organization is doing right your community, being in compliance with the Americans with Disabilities Act (ADA) or Section 508 standards is daunting – especially with the threat of a fine or lawsuit for non-compliance.
Penn in particular nearly made the cut because I really like their keyboard accessibility. It amazes me how few sites provide visible indication of keyboard focus, when it's incredibly simple to achieve (just add a style for a:focus in your style sheet). Penn did this, and consequently it's very easy for sighted keyboard users to keep track of their position as they tab through the page. They also included a keyboard-accessible dropdown menu. However, there are some dynamic features on the Penn home page that really need ARIA markup for full accessibility. They also have a few contrast problems, most notably their slideshow navigation, which is red-on-red:

Monica is the creative force and founder of MayeCreate. She has a Bachelor of Science in Agriculture with an emphasis in Economics, Education and Plant Science from the University of Missouri. Monica possesses a rare combination of design savvy and technological know-how. Her clients know this quite well. Her passion for making friends and helping businesses grow gives her the skills she needs to make sure that each client, or friend, gets the attention and service he or she deserves.

According to the DOJ, “Being unable to access websites puts individuals with disabilities at a great disadvantage in today’s society.” With these words in mind, the DOJ has rapidly adopted the role of web accessibility enforcer. A failure to make digital content, including websites, accessible to all individuals regardless of their emotional, physical, or mental disabilities, can result in hefty fines and class action lawsuits. In short, the DOJ is dedicated to making sure that individuals with disabilities have the same equal access to the benefits that are available online. Creating equal access is only possible if organizations a) understand the requirements of web accessibility, b) know that web accessibility is an obligation under the ADA, and c) make web accessibility a priority. The value that awaits when organizations adhere to digital accessibility laws can be measured in more than dollars and cents.
Case law has been the most helpful in illuminating the implications of the ADA for websites.There have been lawsuits involving companies like Expedia, Hotels.com, Southwest Airlines, and Target as defendants and primarily featuring accessibility organizations as plaintiffs. These cases had mixed results, but each helped clarify the ADA's jurisdiction on the web. 

@Rick, I didn't specifically look at doctype, but Steve Faulkner did in his original article (see the link at the top of this post). He found that 101 of the 130 pages containing role="main" (78%) used the HTML5 doctype, which of course leaves 22% that didn't. I do recommend using ARIA even if using an earlier doctype. Validation is important, but if validation and accessibility conflict, I think most would agree accessibility should trump validation. Assistive technologies that support ARIA landmarks do so regardless of doctype, and otherwise the presence of these role attributes has no ill effects in any user agent.

The Americans with Disabilities Act (ADA) was first passed in 1990. Twenty years later, the US Department of Justice released an update called the 2010 ADA Standards for Accessible Design. These standards cover the design of physical spaces and have been interpreted to include web locations as well, so it can be difficult for the would-be accessible website designer to use them.