Thanks to some great feedback from community members I wanted to clearly articulate the current differences between Clearspace and Clearspace X as well as provide sense of how the products will continue to diverge over time. You can also check out a video on the same topic.
When Clearspace was under development we realized that trying to force a single product into two very different use cases was a bad idea. Since Clearspace and Clearspace X serve different purposes, and have a different set of users and buying criteria, we decided to give them each their own focus. Clearspace is focused on giving people inside organizations a place to "get work done" that breaks down silos between groups, gives everyone a voice and recognition, and keeps people in the loop. Clearspace X, on the other hand, focuses on providing a full-featured online community solution where the needs are around customers getting support, providing feedback, sharing ideas and connecting with other users. This distinction allows our development teams to focus on solving specific business problems instead of worrying about how one product must "boil the ocean" by solving everyone's needs.
The current feature differences stem from different configuration defaults and exposed functionality. Over time the products will diverge more significantly as new features are created for each use case. However, at an architectural level the differences between the products are basically non-existent, and we don't expect the two products to diverge architecturally in any meaningful way.
The two products contain different default profile fields: Clearspace contains 'location', 'title', 'phone number', 'biography' and 'expertise'. Clearspace X contains 'location', 'occupation', 'biography', 'expertise', and 'homepage'.
Create Blog Permission
Registered users are given permission by default to create a blog in Clearspace but are not allowed to create a blog unless given permission in Clearspace X.
Anonymous / guest users are allowed to view content in Clearspace X by default, but in Clearspace that permission is off which forces users to first login before viewing any content.
Private messages are enabled by default in Clearspace X and disabled by default in Clearspace.
Blog trackbacks are off by default in Clearspace but on by default in Clearspace X.
Blog pinging is enabled by default in Clearspace X and disabled by default in Clearspace. Blog pinging is a process that happens behind the scenes in most blog software. When enabled, your instance will send an XML-RPC ping to weblogs.com, Google blog search and Technorati, but only if blog pinging is enabled when a new blog post is created / published on your system.
Email addresses on user profiles are hidden by default in Clearspace X and are visible by default in Clearspace.
Clearspace X uses the word 'Community' when describing the containers for content while Clearspace uses the word 'Space'.
Clearspace X uses a different design than Clearspace. The difference is controlled by using jive-external.css versus jive-internal.css.
More Differences Over Time
Over time there will be certain features or changes that only make sense in one or the other product.
Reputation and Recognition
The way that the reputation and recognition system work will change over time as each product gets a more focused version of the system.
This type of functionality only makes sense in Clearspace for most customers.
Integrations with other systems may only make sense in one use case or the other.
Clearspace and Clearspace X have different purposes and are meant to solve different problems. So it only makes sense that we want the respective development teams to be thinking about those problems as they further refine the product. The current differences are primarily focused on configuration to best fit the problem being solved by each product, but these differences will continue to grow as new features are added that are unique to its intended use case.