Eugene's observations

It's been publicly available for a few months and in public beta test for several before that so all the teething troubles that are going to be found and removed probably have been.  So should you upgrade ?  

If you are reasonably competent with administering your computer then I suggest you should as the benefits are certainly worth having.  There are, however, a few points to follow before the upgrade to save yourself a pile of pain.

1. Run the Upgrade Assistant.   This will draw attention to any incompatible hardware or software.  The Assitant will appear in your system tray as long as you have the fiollowing updates installed: for Windows 7 (KB3035583 and KB2952664) and for Windows 8.1 (KB3035583 and KB2976978).
   
   
2. Perform routine housekeeping.  You do this every quarter anyway, right ?  The key things would be to uninstall any programs and browser helper objects that you no longer use.  Now delete the contents of the %Temp% folder, browser cache files, and the recycle bin. Perhaps the Downloads folder too.
   
   
3. Take an image of the system partition - something I have had cause to be thankful for having on several occasions.  Also check that your last regular file backup is recent, complete, and recoverable.  Ensure these potential saviours are not on the disk that Windows 10 is to be installed on, and physically disconnect the media after they're written.  The image will be invaluable should things go wrong, and the backups too could be helpful depending on the way in which an upgrade fails.
   
   
4. Uninstall internet security, anti-virus, and firewall software just as soon as you have confirmed you have the installation kit, product keys or online account details necessary to enable it to be reinstalled in a later step. 
   
   
5. Record the activation keys or serial numbers of any programs that require them.  Make sure you have a note of any passwords necessary to reinstall an application should it be necessary. 
   
   
6. Save current device drivers.  It is unlikely these will be needed as Windows 10 does a good job most of the time, but it is always prudent to stash these somewhere. 

Now you're ready to kick off the upgrade.  Make sure the power cable is connected and if possible, provide a wired internet connection to speed things along.  There are a couple of screens to go through but after 5 - 10 minutes you are ready to get on with something else and pop back in 2 to 5 hours depending on the speed of your computer and the internet connection.  After the task is complete you have a few post upgrade tasks to complete.

1. Reinstall your internet security, virus protection, and firewall software.
   
   
2. Go to Settings and update Windows then restart when instructed. 
   
   
3. If you have wigets or gadgets they will probably need to be installed again.  You may like to check that the most important programs are working as they should.  
    
4. Check that the default programs are as you wish; make sure network folders are accessible; and confirm that System Restore is active.
    
5. Take your first backup of the new system.  If coming from Windows 7 see if File History is better than your old program.

Now you're ready to check out the new features and have some fun with them.  Note that to get anything from the Windows Store - even the free apps - you will need a Microsoft account.  This is also necessary to make use of the (free) 15GB OneDrive storage that can be used for sharing photos etc.  You can use your existing email address to do this.

There will be a new app installed called 'getting started', this is an introduction to the new features of Windows 10 and certainly worth a gander.