Shrinking budgets + skyrocketing subscription fees = UC boycott of NPG.

Economic recovery has not yet made its presence felt at public universities in California. (Indeed, at least in the California State University system, all things budgetary are going to be significantly worse in the next academic year, not better.)
This means it's not a great time for purveyors of electronic journals to present academic libraries in public university systems with big increases in subscription prices. Yet Nature Publishing Group has, apparently, done just that by some 400%. And, as noted by Christina Pikas and Dorothea Salo and Jennifer Howard in The Chronicle of Higher Education, the University of California system has decided that what NPG is offering is not worth the asking price.
Which means a system-wide boycott of NPG journals is being organized, as outlined in this letter (PDF) from the executive director of the California Digital Library, the chair of the University Committee on Library and Scholarly Communication, and the convener of the University Librarians Council.
Interestingly, the boycott goes further than just encouraging UC libraries to drop their costly subscriptions to NPG journals. From the letter:

[U]nless NPG is willing to maintain our current licensing agreement, UC Faculty would ask the UC Libraries to suspend their online subscriptions entirely, and all UC Faculty would be strongly encouraged to:

• Decline to peer review manuscripts for journals from the Nature Publishing Group.
• Resign from Nature Publishing Group editorial and advisory boards.
• Cease to submit papers to the Nature Publishing Group.
• Refrain from advertising any open or new UC positions in Nature Publishing Group journals.
• Talk widely about Nature Publishing Group pricing tactics and business strategies with colleagues outside UC, and encourage sympathy actions such as those listed above.

One of the benefits of a big university system is supposed to be increased bargaining power. If UC faculty take the boycott seriously, NPG is going to feel it.
One bullet point that I think ought to be included above -- something that I hope UC faculty and administrators will consider seriously -- is that hiring, retention, tenure, and promotion decisions within the UC system should not unfairly penalize those who have opted to publish their scholarly work elsewhere, including in peer-reviewed journals that may not currently have the impact factor (or whatever other metric that evaluators lean on so as not to have to evaluate the quality of scholarly output themselves) that the NPG journals do. Otherwise, there's a serious career incentive for faculty to knuckle under to NPG rather than honoring the boycott.
There is some gesture in this direction in the letter:

We clearly recognize that the consequences of such a boycott would be complex and present hardships for individual UC researchers. But we believe that in the end, we will all benefit if UC can achieve a sustainable and mutually rewarding relationship with NPG. In the meantime, UC scholars can help break the monopoly that commercial and for-profit entities like NPG hold over the work that we create through positive actions such as:

• Complying with open access policies from Federal funding agencies such as the NIH (http://publicaccess.nih.gov).
• Utilizing eScholarship, an open access repository service from CDL (http://www.escholarship.org/publish_postprints.html).
• Considering other high-quality research publishing outlets, including open access journals such as those published by PLoS and others.
• Insisting on language in publication agreements that allows UC authors to retain their copyright (http://osc.universityofcalifornia.edu/manage/retain_copyrights.html).

This is all encouraging. But an explicit impact factor moratorium for at least the duration of the NPG boycott would be even better. (Who knows, maybe it would convince hiring, retention, tenure, and promotion committees that they could make reasonable decisions even without leaning on such metrics, even in the event that NPG comes back with a reasonable price for online subscriptions.)
Indeed, from the Chronicle of Higher Education article, it sounds like at least one of the organizers of the boycott recognizes that this might be the right direction for the UC to move:

Keith Yamamoto is a professor of molecular biology and executive vice dean of the School of Medicine at UC-San Francisco. He stands ready to help organize a boycott, if necessary, a tactic he and other researchers used successfully in 2003 when another big commercial publisher, Elsevier, bought Cell Press and tried to raise its journal prices.
After the letter went out on Tuesday, Mr. Yamamoto received an "overwhelmingly positive" response from other university researchers. He said he's confident that there will be broad support for a boycott among the faculty if the Nature Group doesn't negotiate, even if it means some hardships for individual researchers.
"There's a strong feeling that this is an irresponsible action on the part of NPG," he told The Chronicle. That feeling is fueled by what he called "a broad awareness in the scientific community that the world is changing rather rapidly with respect to scholarly publication."
Although researchers still have "a very strong tie to traditional journals" like Nature, he said, scientific publishing has evolved in the seven years since the Elsevier boycott. "In many ways it doesn't matter where the work's published, because scientists will be able to find it," Mr. Yamamoto said.

(Bold emphasis added.)
Scientific publication, after all, isn't just about keeping score. It's also about communicating findings, ideas, techniques, and conclusions. And NPG surely has no monopoly on the technologies by which that communication can -- and will -- take place.