Here is an updated summary of cost estimates for Google Apps

Hardware Costs – $0

Since Google Apps is hosted, there is no need to purchase hardware…

Upgrade Cost – $0

Google Apps for Education is a collection of web applications hosted by Google.  Google performs all updates, therefore there is no cost for updating

Mobile Costs – $?

Google has excellent free mobile versions of most of its applications including Blackberries.  Blackberry Enterprise Server may still be needed.

Support Cost – $?

Google has excellent online documentation and many faculty, students and staff are already familiar with Gmail. Other institutions have noted that Google’s help forums have provided many answers for their users.  Main challenges here are different workflows and user interfaces (UIs).

There will need to be regular training sessions to introduce the community to Google’s approach to email, calendaring and groups.  The frequency of these sessions should be comparable to those offered when we redid the college website, though may need to be more extensive and more frequent.

Support costs will depend on whether we decide to support the use of Gmail and calendaring tools in desktop client apps like Outlook and Entourage or whether we decide to require everyone to use web interfaces. Restricting support to web-based UI may require additional initial retraining but would probably reduce costs in the long term since we won’t have to support multiple desktop applications.

Migration Costs – $?

Google provides free tools for migrating from Microsoft Exchange.  Brown University migrated most of their users over the course of a couple of months.  Other institutions have done the migration all at once.  While there are vendors that offer migration services, we will likely be able to do the migration ourselves.

Staff Costs – $?

Since Google Apps is hosted, there are no server maintenance costs…  Most of the staffing costs will be in training people to learn how to do the same work in Google Apps as they did with Exchange as well as the staffing resources required to do the migration.

Recovery Costs – $?

Since Google Apps is hosted, we are not able to recover data ourselves beyond what can be done in the administrative interface to Google.  Postini will allow administrators to recover deleted mail from the past 90 days.

Google does make an effort to ensure content you put into its applications can be backed up (see: Backup your Google Apps Data).  Google has also shown a commitment to ensuring users can migrate their data with its Data Liberation project.  Google itself relies on synchronous data replication to ensure nothing is lost (see: Google Apps Now Disaster Proof).

Licensing Fees – $5,700 – 18,500 per year

Google Apps for Education is free.  This means there are no licensing costs for using it.  However in order to get spam filtering and tools for recovering lost email, we would need to purchase a license for Postini which costs $4 per user per year.  Here’s an estimate of total licensing cost for various levels of Postini:

Middlebury College:
2400 – students x $4 = $9,600
300 – faculty x $4 = $1,200
850 – staff x $4 = $3,400
3550 – total users x $4 = $14,200

MIIS
800 – students x $4 = $3,200
150 – faculty x $4 = $600
115 – staff  x $4 = $460
1065 – total users x $4 = $4,260

Total licensing costs
Midd/MIIS faculty/staff = $5,660 per year
Midd/MIIS faculty/staff/students = $18,460 per year

Testimony from other Institutions

A number of institutions have claimed that switching from Microsoft Exchange to Google Apps has saved them money.  See:
Brown > CIS > GoogleAppsGoogleApps@Brown – Google Applications for Education