Some recent articles
Judah Galinsky has an article in Tsiyon 72, 4 (2007), continuing his work on R. Asher ben Yehiel in Toledo. In this article, he brings together some of the strands of his recent work by demonstrating how the Rosh influenced local practices of tax-paying and charity in order to achieve a shift in values, towards communal support of learning Torah Lishmah.
Tsiyon 73 (2008) includes an article by Prof. Simcha Emanuel surveying halakhic discussions of Gentile wet-nurses. Jews in medieval Europe used wetnurses frequently, and Jewish ones were more expensive. Emanuel discusses the halakhic issues that arose, including the question of whether the nurse would be allowed to eat non-Kosher foods. The only Halakhist to really discuss this question was R. Isaac Or Zarua, but apparently, French Jews in Paris and Sens were actually quite strict about this. Emanuel suggests that it was the Or Zarua's teachers in Paris and Sens who taught him this stringency, but they failed to mention it in their own halakhic works. Why?
One answer that Emanuel hints to, but does not pursue, is that this was a position held by only part of the community in these cities - and not by the Tosafists themselves. This opens the door to interesting questions regarding the position of authority that the Tosafists held in their own communities (akin to the debate about the authority of the Tannaim).
The answer he gives is that, as it turns out, Tosafists do not always discuss their actual practice when commenting on Talmudic texts. They do it frequently, to be sure, and thus allow historians of Halakhah to keep themselves busy. But not always - sometimes they are content to focus on the Talmud, ignoring the ramifications for their communal practice.
Of course, it's possible that their failure to discuss this particular custom may have been because of how uncomfortable it made relations with Christians at times:
בדבר הזה אין אנו מודיעין למלכות
Professor James Diamond was kind enough to send me a PDF of his article 'King David of the Sages: Rabbinic Rehabilitation or Ironic Parody?'. The Talmud tells some very strange stories about King David, which leave you wondering whether you're supposed to admire or revile the biblical figure. Diamond suggests that they are best read in an ironic key, which allowed the rabbis to voice their criticism of his actions while preserving his stature in the eyes of the masses.