Dell's confusion over tablet format has ended, as it retired its part-tablet and part-smartphone, the 5-inch Dell Streak, in favor of bigger tablets.

Dell announced the sudden demise of the Dell Streak 5 on Web site with the words: "Goodbye, Streak 5. It's been a great ride."

The pulling of the plug on Dell's first Android tablet comes just after it released a 10-inch Android Honeycomb tablet called Dell Streak Pro 10 in China.

Also, at CES 2011 in January, Dell unveiled a 7-inch Android tablet under the moniker Streak 7.

Dell Streak 5, the first tablet from the Dell camp, featured Android 2.2, or Froyo, and was powered by a Qualcomm Snapdragon 1GHz processor. It sports a WVGA screen with 800x480 screen resolution. It has 512MB RAM and comes with a 16GB pre-installed MicroSD.

The phone weighs 7.7 oz and is 0.4-inch thick. It also offers a 5MP rear-facing and VGA front-facing cameras. The tablet is also a full-fledged GSM phone.

The 5-inch factor was an oddball in the midst of other form factors which had caught the fancy of Dell's competitors. Most of the current breed of tablets flaunt 7-inch, 8.9-inch. 9.7-inch and 10.1-inch form factors.

Thus Streak 5 was too small to be tablet. As a smartphone it was rather big at 5-inch as the most recent breed of smartphones like Samsung Galaxy S2, HTC Thunderbolt and Motorola Photon, sport 4.3-inch display sizes. The upcoming smartphones are expected to push the limit to 4.5-inch displays.

It is rumored that upcoming phones like HTC Holiday and Samsung Celox will have 4.5-inch displays. Compared to this Streak 5 was still bigger than the most recent smartphones.

Also Dell Streak 5's pricing strategy went amiss as its unlocked version was launched at $550, which was $50 more than the entry version iPad.

Here are some of the top tablets from various makers in different form factors:

7-inch:

RIM Playbook, HTC Flyer, Samsung Galaxy Tab 7, Dell Streak 7 and ASUS Pad MeMo

8.9-inch:

LG G-Slate, Samsung Galaxy Tab 8.9

9.7-inch :

Apple iPad, HP TouchPad

10.1-inch:

Samsung Galaxy Tab 10.1, Motorola Xoom, Toshiba Thrive, Lenovo IdeaPad K1, Acer Iconia Tab A500