I have been using Microsoft OneNote for a little over a year now and have finally decided to take a moment to write on my experiences with it.
For those of you not familiar with OneNote, its Microsoft's offering in the notebook replacement arena. Much in the same vein as Evernote, its primary purpose is to assist you in your daily note taking, something that is quite common when you work as a Programmer. OneNote is a part of the Microsoft Office suite, and while I have had access to it at work, I did not really give it a chance until I picked up my Windows Phone back in May of 2012.
Microsoft has made a big push in the last few years to make their Office suite more avaliable to consumers, outside of the traditional Enterprise setting. Starting with Windows Phone, and then with their forays into products such as Office 365 and SkyDrive to compete with Google Docs and Google Drive OneNote has been pushed from a once niche product to the forefront. Microsoft Office Home and Student 2013 come with OneNote and new Windows 8.1 Tablets smaller than 10.5in come with Home and Student 2013 preloaded.
My first real experience with it was via Windows Phone which contains a native App that allows you to edit notes and then store them to Microsoft's SkyDrive service. You can then edit the notes using the SkyDrive/Office 365 WebApp, or link your desktop version of OneNote to SkyDrive and have one centralized place where all of your notes are uploaded and then synced down to your devices. This integration was a huge selling point to me as it allowed for central storage of my thoughts and notes in a way that was consistent and fluid.
The tool itself is very powerful, allowing for various forms of input via Keyboard, Voice, or Digitizer. It integrates extremely tightly with the rest of the Microsoft ecosystem, specifically with Outlook/Exchange and Sharepoint which allow for seamless flow between Office Apps.
That being said the tool does leave a lot to be desired, for one its document formatting tools leave a lot to be desired. In its defense I think they are trying to market it as a place to jot your notes with the intention that you open up into Word once you want to do some heavy formatting. However having editable Styles (specifically allowing for the "Code Style" to be modified) would be a huge boon.
Also as with most tools it is only as good as the experience of the end user of the tool. While I do not believe the learning curve is high on this tool, good note taking skills, which a sizable portion of people lack, are crucial when using a tool such as this.
The final complaint was the high complexity of a recovery when something "goes wrong". I recently ran into an issue in which somehow my unfiled notes section became corrupted during a Sync between my devices. The recovery process involved me creating a new section and copying out the affected pages. While a simple task for me, I could see how it would be daunting for your average end user.
What continues to bring me back to this program is the integration and cloud aspect of the program. The fact that there is a single experience between multiple devices and that your data follows you everywhere is a huge productivity boost and encourages use of the product though ubiquitous use. If you have not already tried OneNote, or had tried it in the past and given up, give it a shot today and experience what an integrated solution offers you.