It seems that there is no big difference between Hoover TaskVac and Linx, only tiny ones.
Hoover TaskVac vs Linx
images from manufacturer

The Hoover Linx BH50010 is designed for Household use while the TaskVac CH20110 is for Commercial use. According to the reply from Hoover customer service, both units operate the same, however, model CH20110 has a motor that is designed for commercial use.
The Linx carries a 2 year limited warranty while the TaskVac carries a limited 1 year commercial product warranty.
And there is difference on the color scheme.

Compare Hoover TaskVac and Linx Specs Side by Side

	Hoover CH20110 TaskVac Compact Upright Vacuum	Hoover Linx Cordless Stick Vacuum Cleaner BH50010
Design	Stick	Stick
Price		$179.99 at Hoover.com on September 1, 2014
Bagged or Bagless	Bagless	Bagless
Dirt Bin Capacity	Not Specified	Not Specified
Battery Life Indicator	Fuel Gauge	Fuel Gauge
Fully Charge Indicator	Yes	Yes
Power Source	Battery Operated	Battery Powered
Battery Type	Lithium Ion	Lithium Ion
Power	18 Volts	18 Volts
Batter Life		about 15 minutes
Charge Time	about 3 hours	less than 4 hours
Motorized Brushroll	Yes	Yes
Brushroll On/Off	Yes	Yes
Washable Filters	Yes	Yes
Headlights	No	No
HEPA Filtration	No	No
Weight	8 pounds	7.3 pounds
WindTunnel Technology	Yes	Yes
Nozzle Width	11"	11"
Height Adjustment	Self Adjust	Self Adjust, No Manual Settings
Brushed Edge Cleaning	Yes	Yes
Included Tools	No tools But comes with an extra 2-layer micro filter.	No
Handle	Fixed Extreme Recline Handle	Fixed Extreme Recline Handle
Cleaning Wand	No	No
Clear Dirt Cup	Yes	Yes
Bottom Release Dirt Cup	Yes	Yes
Clear Nozzle Window	No	No
Hose	No	No
Color	Black and Dark Grey	Black and Glacier Blue
Self-propelled	No	No
Low Profile Base	Yes	Yes
Full Bin Indicator	No	No
Dirt Finder	No	No
Warranty	Limited 1 year commercial product warranty	2 year limited warranty
Manual	download manual	User Guide

If you know other difference between these 2 hoover stick vacuum cleaners, please share your reviews below.