Samsung's flagship 'phablet' has already been available to AT&T, Sprint and T-Mobile subscribers for some weeks now, but the Galaxy Note 2 is now also available for pre-order on Verizon's website, equipped with the latest Android firmware update.

Samsung has just announced that the 5.5-inch device has already surpassed the 5 million mark in terms of sales and the Verizon launch could make it the best selling phablet of 2012.

Samsung said on its website that the Note 2 hit that target in only two months of its release - selling two million since the start of November alone when it was made available to US customers.

The previous version of the device, the Galaxy Note, took five months to reach those numbers and Samsung predicts the device could sell as many as 20 million units - around double that of its predecessor - thanks to a partnership with 260 carriers around the world.

However, even those figures pale in comparison to the Galaxy S3 which sold 20 million units in the first 100 days after its launch.

But the difference is that the market for 5-inch to-7-inch smartphones is significantly smaller than that for regular-sized devices and the sales figures for the Note 2 defy many industry expectations.

The Note 2 comes with a 1.6GHZ quad-core Exynos chipset with 2 GB memory and features an 8MP camera. It also comes with a a new S Pen stylus with over 1,000 pressure levels and a 3,100 mAh battery capable of keeping it awake through more than two days of moderate usage.

Verizon's release, which incorporates Android 4.2 Jelly Bean, also allows multi-window multitasking that involves running two apps with full functionality on half the screen and alternating between them by drag and drop.

The sales figures are certainly impressive, however, the 5-inch HTC Droid DNA, also recently released to US customers, could give Samsung's device a run for its money - as could Google's LG-made Nexus 4.

The 5-inch Droid DNA also has a quad-core processor, 2GB of RAM and boasts a 1920x1080pixel display - the first full HD smartphone on the market.

 The Nexus 4 is similar in most respects but only manages 1280x768pixels on a 4.7-inch screen - better than the Note 2 but not at impressive as the Droid DNA. The Nexus 4 is currently sold out due to overwhelming demand but is unlikely to hit anywhere near the Note 2's sales figures having only been released two weeks ago.

With the year winding down, the Verizon release of the Note 2 could help secure Samsung the best selling smartphone with the S3 as well as the best selling phablet of 2012.

Verizon's Web site currently has the Note 2 available for pre-order for $299 on a 2-year contract. There is no ship date available as yet.