google is continuously rolling new products through labs --> beta --> production (yet to see one product leaving beta stage). a list of their products and technologies can be seen here

so far i tried out blogger (b4 google bought it) then got an invite from google for a gmail account and like the yahoo mail account it's proving to be the key to all the other google services like google chat, personalised search page/homepage, search/news alerts, google pages (real-time gui for creating webpages....using the browser), google calendar (allows automatic inclusion/import of national holidays of various countries and exports to iCal format for desktop clients supporting the format)

google uses AJAX very heavily and hence it's more pleasurable to use the services....at the same time, they do expose a lot of their internal code through API's so people can also learn from the examples

yahoo search gives more relevant results for the term "diabolic preacher" than google....am thinkin of givin yahoo it's fair share of credit...i guess i do that already...have the knack of using services which they go ahead and buy. :)