YouTube, Google Finance, Google Maps, Blogger, Google Docs, Google Groups, Google Reader, Google Talk, Google Voice, Google Calendar, Chrome, and the entire Android platform are all things that I use on nearly a daily basis. Most, if not all of those are the leading product in their field. Companies by the boatload switch to exclusive use of Google Apps for almost all of their needs, and there's a reason behind it.
That's not to say that they're flawless. Google Video was pretty terrible until they killed it for YouTube. Knol is a pretty big failure. They never really did anything with Picasa on the web side of things (I thoroughly enjoy the desktop app however). They really dropped the ball on Wave in terms of marketing and deployment. Wave in particular saddens me, because it could have so easily gone the other way and been an excellent successor to email. And I'm sure they have hundreds if not thousands of products that we never hear about and never will see the light of day.
But saying Google has only succeeded in Search and E-mail is just silly.