No, there is no way to view those notes unless they are explicitly added by the developer.
Developers can choose to publish them and they will be included in the description of the application. If you are not seeing anything then the decision was made to not include them. If any contact information is provided you can always try to reach out and ask what has changed.
Being an enthusiast mobile app developer I agree with your intention of the question. It is good practice to provide information on the updates in the about field, for several reasons.
1. Let the user know what has changed
To the courtesy of your users, a developer should provide information on what changed on updates. In other professional software developments you can never change an application without letting the user know what the scope of the change is. This is especially important if some functionality have changed, which change the user experience or workflow sequence. On mobile the user will be notified if the app starts to use other services than before.
2. Communicating a serious intention
As a phone app user I can often differentiate serious app developers from not so serious ones. It all boils down to trust of the application and the developers, since Marketplace is often the only source I have to validate the app. How can I tell if this app is not only useful but is also trustworthy and do not harm my phone? Of course Microsoft checks the app before submission to the public, but on can never be to certain. In my humble opinion a credible update log of changes is more trustworthy than no log at all.
3. Convention
It is more and more becoming a convention among mobile app developers to include an update log. When you update applications which was developed from serious mobile application producers like Rovios Angry Birds or Microsoft Skype, there is an update log (or release notes) accompanied.