I switched a bunch of my Yahoo services to Google starting a year or so ago. I also switched my hosting to asmallorange.com.
As part of this process I use Google Apps extensively, including for my email. In fact I run a small business on Google apps.
One thing I have never done though is bought a domain from Google who I believe subcontracts to enom or godaddy. The pricing is $1O which includes full dns management, private registration and domain locking if you need it. Pretty good deal – especially with Google’s name behind it.
