The short of it (covered in depth by Michael Eisen, and Razib tipped me off to the issue) is that Carolyn Maloney, a congresswoman funded by Elsevier, which is a major for-profit publishing company, is trying to pass the Research Works Act, which would deny Americans free access to research funded by taxpayer money. Currently, any research funded by the National Institute of Health must be made freely available to the public 12 months after publication. You can see why for-profit publishing companies do not like this policy. After 12 months, they can no longer turn a profit on any research they publish that was funded by the NIH. From Eisen's post:

The policy has provided access for physicians and their patients, teachers and their students, policymakers and the public to hundreds of thousands of taxpayer-funded studies that would otherwise have been locked behind expensive publisher paywalls, accessible only to a small fraction of researchers at elite and wealthy universities. The policy has been popular – especially among disease and patient advocacy groups fighting to empower the people they represent to make wise healthcare decision, and teachers educating the next generation of researchers and caregivers. But the policy has been quite unpopular with a powerful publishing cartels that are hellbent on denying US taxpayers access to and benefits from research they paid to produce. [...] So I urge you to call/write/email/tweet Representative Maloney today, and tell her you support taxpayer access to biomedical research results. Ask her why she wants cancer patients to pay Elsevier $25 to access articles they’ve already paid for. And demand that she withdraw H.R. 3699. Representative Maloney: Twitter: @RepMaloney @CarolynBMaloney Phone: 202-225-7944 FAX: 202-225-4709 Email: Use this form

EDIT: Thanks to commenter Cogitari for pointing out something I originally meant to put in this post, which is that writing to your OWN congressperson may be your best bet at getting a response. You can find your congresspeople by going to house.gov and senate.gov and using the search tool in the top right corner of each.

My fellow SciAm-blogger Janet has a post up discussing the ethical issues involved in the proposed act:

Let’s take this at the most basic level. If public money is used to fund scientific research, does the public have a legitimate expectation that the knowledge produced by that research will be shared with the public? If not, why not?

Kevin Zelnio has a good discussion of the topic up on his blog, and there's also a roundup of blog posts on the topic here.