Toshiba is releasing one high-capacity HDD after another lately. Today, the company announced [PDF] two new hard discs, which are poised to find their way into our notebooks very soon, the MK7559GSXP (750GB/pictured) and the MK1059GSM (1TB). The 750GB model is the world’s most capacious 2.5-inch/9.5mm high HDD. Toshiba released its predecessor (holding 640GB) back in September last year.

The new HDD is a two-platter that rotates at 5,400rpm, has a seek time of 12ms and boasts an areal density of 541.4G bit/in2, which Toshiba says is the highest in the industry. The 2.5-inch, 1TB MK1059GSM is a three-platter that’s 12.5mm thick and features the same speed and seek time.

Toshiba already offers samples of the 1TB HDD to certain manufacturers (samples for the 750GB model will be available next month). The final versions of both drives are scheduled to ship to manufacturers in the second and third quarters of 2010.