As a platform for customized workflow automation, Google Apps is still far from where Lotus Notes was,
way back 20 years ago, even with it's still immature v3.
Yet, now Google Apps is just starting to rapidly
gain some of the magic of that early Lotus Notes
-- and it is exciting now, to watch the fast progress
of Google Apps -- with the new GUI Builder,
the expanding Google Apps Script and all the APIs, and with it's cross-platform access to online centralized data (all parts of the early Lotus Notes).
Here is what is missing still, from Google Apps as it approaches the worthy path well-trod by Lotus Notes...
customizable "document forms" to easily specify unstructured data models, with data-fields and automation for data-flow -- and for easy user-creation of numerous data "documents", as the basic collection of data-entities;
an unstructured back-end "object store", able to automatically persist any number of unplanned and unstructured data-entities, each holding unstructured data-items -- with no "nuts and bolts" programming needed, and all relying solely on "labels" to indicate all data attributes (Note: Google's "Big Table" seems primed to easily handle this same unstructured data-base approach, with expected improvements in performance -- see: goo.gl/J4C5q );
a easy and powerful "view" mechanism, to show easily-customized and flexible tables of common data from across multiple collections of specified "data entities", with drill-down and sorting capabilities all built-in -- all with no "nuts and bolts" programming needed.
In case you are curious now, about Lotus Notes
-- here's a great introduction...
http://www.nsftools.com/misc/WhatIsNotes.htm
So, it's easy to expect, that Google Apps will rapidly progress, to include and provide all the above "missing" elements -- by 2013, maybe, if Google aims for that -- and then Google Apps will have the wings needed, to fly with rapid development of high-quality customized workflow automation applications!
Go Google!