It has been suggested in various writings that the newly issued Microsoft patent on an XML-based document would somehow resolve Microsoft's woes against i4i. This is most unlikely. A patent grants only rights to exclude others from practicing a claimed invention, and creates no right at all to practice the claimed invention. It is quite possible to obtain a patent governing a novel and unobvious variation of an existing patented technology. While the second patent would grant its owner the right to exclude people (including the first patent owner) from practicing the variation, it would grant no right to practice the variation if the variation also infringed the first patent.
Of course, it may be the case that the first company may want to practice the variation as well, in which case a cross-licensing deal might be worked out. But the issuing of a new patent on related technology does not, itself, help Microsoft out of its box unless the new technology does not infringe the i4i patent.