One of the powerful ways to leverage SharePoint and BPOS's SharePoint Online Standards is with Content Types.  SharePoint Content Types allow you to define a standard set of metadata about individual pieces of content.  In a given Document Library you can have many, many content types.  For example, you might have a library called Customer Documents and within that library you might have three content types - "Contracts"  "Project Documents" and "Time Sheets".  In the Contracts Content Type you would have a set of defined columns. Some of these columsn would be custom - such as "Customer Name" but others you'd pull directly from SharePoint Core Columns such as those having to do with mailing addresses.  As a part of every SharePoint site you should create the content types that you will use with your document libraries. This will allow you to enhance search, workflow, usability, findability and have create views that do the heavy lifting of manual foldering.

In BPOS to get started with content tpes you need to first go and ahead and see what Microsoft has built for you -  to do this go to Site Actions > Site Settings > Site Content Types.

Next - Click on any Content Type - as an example I have created "Proposals" - you probably will not see that option so choose Document. 

Explore the columns that make up the Content Type. Then add a new or add from existing. The next screen shot adds a new column.

Adding a new column is easy - I like to use Calculated Columns from time to time. I am going to use a Calculated Column because I want the "Customer" to display as an aggregate or combination of multiple columns.  This makes for easy viewing - I can combine multiple values into a single text string value.

Here's where I add my formula. The result of this formula will space with spaces "Company Phone Phone" in the Customer field throughout my list.

This is a nice summary - but to work with columns and Content Types you need practice.  Try making a view of your own with your BPOS SharePoint Online Standard sites.

More Reading:

http://msdn.microsoft.com/en-us/library/ms472236.aspx

LearnVu.com has an awesome screencast on Access 2010 Services (which runs on the next version of SharePoint or SharePoint Online).  Go check it out and see fully functional access reports, forms and DB's running natively from SharePoint 2010 in the browser!

Here's the link  http://www.learnvu.com/blog/post/Creating-Web-Applications-in-Access-2010-and-SharePoint-2010.aspx

One of the greatest BPOS features is the quarterly updates - this suggests a more contemporary approach to on-going software development pioneered by Google.  Part of the power of BPOS is the regular updates that deal with issues and add functionality to improve the overall user experience.  With SharePoint 2010 launching in 1st or 2nd Q 2010, BPOS won't be far off in completing its migration to the new 2010 feature set.  We will be watching this migration, version upgrade very carefully and documenting anything an everything we find about what an end user or service administrator might need to do prior to and after the upgrade.  There might be something as simple as modifying the master page to include a new Terms and Conditions Reference, or a change / update to your existing workflows.  At this point, we don't have all the details but the list is starting to form.  Look for something in the coming months.