Voice dialing might be convenient, but it isn't going to make you any safer while driving. The hands-free laws are political sophistry. There is no evidence that it improves safety. In fact, there have been many studies that have shown hand-free calling is equally as distracting as holding the phone. It isn't the physical constraints, but rather a cognitive task that causes the distraction.
As a bonus, it has been shown that driving while on a cell phone is comparable to driving while legally drunk.
http://www.ingentaconnect.com/content/hfes/hf/2006/00000048/00000001/art00018
http://books.google.com/books?hl=en...EMXJ&sig=NGXoE5dN7ODQfssHJ6ka2tAlasU#PPA64,M1
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=570222
http://ppc.uiowa.edu/driving-assess...ownloads/Final_Papers/PDF/5_Strayerformat.pdf
As a bonus, it has been shown that driving while on a cell phone is comparable to driving while legally drunk.
http://www.ingentaconnect.com/content/hfes/hf/2006/00000048/00000001/art00018
http://books.google.com/books?hl=en...EMXJ&sig=NGXoE5dN7ODQfssHJ6ka2tAlasU#PPA64,M1
http://papers.ssrn.com/sol3/papers.cfm?abstract_id=570222
http://ppc.uiowa.edu/driving-assess...ownloads/Final_Papers/PDF/5_Strayerformat.pdf