Some cell phones support phone words in the dialing environment (e.g. Blackberry qwerty phones).
Some support phone words in the texting environment (e.g. in Samsung Galaxy S phones, you can specify a phone word as a text message recipient, the phone accepts it and even writes its numerical equivalent under it).
Other phones simply give an error message if you write a phone word for a text message recipient (e.g. Sony Xperia).
I think it would be great if BestBuy specifies for each cell phone whether it supports phone words in the dialing environment and/or in the text messaging environment.