On December 4, Canon U.S.A. announced a trio of new desktop inkjet devices: the PIXMA iP7220, an A4-sized single-function inkjet printer, and the PIXMA MG5420 and PIXMA MG6320 A4 inkjet all-in-ones.With the new hardware, Canon is rolling out a new generation of ink tanks: the PGI-250 and CLI-251 series. The OEM is taking a new