Hoover UH70210 and UH70211 are 2 of the Hoover T-Series WindTunnel Pet Rewind Bagless Upright vacuum cleaners. They have pet tools and filtration that are made specifically for pet hair and odors.

It seems that there is no difference between Hoover UH70210 and UH70211 except for the price tag and colors.
UH70211 vs UH70210
images from manufacturer

Price: UH70211 is $10 cheaper than the UH70210.
UH70210 is priced at $159.99 while the UH70211 is priced at $149.99 at hoover.com. (prices checked on June 14, 2013)

Color:
The UH70210 is blue whereas the UH70211 is grey.

Learn more by reading manuals of UH70210 and UH70211:

UH70210 Manual:
http://hoover.com/file/574/

UH70211 Manual:
http://hoover.com/file/575/

If you know more difference between Hoover UH70211 and UH70210, please share below.