We have received the following information from the FECYT indicating that, as happened last year, the 2011 JCR data are not definitive:
"Thomson Reuter we just communicate that data provided in the 2011 JCR, published online on June 29th, are not definitive. These data are being updated weekly with the introduction of new journals or updating data. All these changes will be visible and will be definitive in the online JCR online in the update of next September."
The new 2011 JCR, Journal Citation Reports Edition 2011, has already been published
On 28 June the new JCR for the year 2011 was published. The JCR from Thomson Reuters calculates this year's impact factor of 10677 publications, and 528 of them received it for the first time.
JCR presents statistics dating from 1997 onwards. The usefulness of the JCR is the comparation of journals within their subject categories (impact factor of journals).