Microsoft has a problem, and it’s with context-sensitive search. Or, more accurately, it’s with users not understanding context-sensitive features like search.

The initial release of Windows Phone 7 included a context-sensitive search button, which apps used in lieu of an icon in the software to provide search capabilities. If the app didn’t support search or the user was on the Start screen, the hardware button simply launched the Bing app. Unfortunately, while this streamlined the interface, some users were never quite sure whether hitting the button would begin a search or open up Bing. As a result, the Windows Phone 7.5 “Mango” update removed the concept of context-sensitive search and transformed the search button into a dedicated Bing button, leaving apps to include a search option in the user interface (UI).

Fast-forward a year to the release of Windows 8, which features four context-sensitive Charms: Search, Share, Devices, and Settings. While the Charms always have similar functionality, the exact contents of each Charm will change depending on which app is currently in use. If you’re on the Start screen, search will default to searching apps. However, if you’re using the Mail app, the same button will search your emails. The same goes for the other three Charms. While some third-party apps have ignored the Charms in favor of a separate settings screen – or, at the very least, a Settings Charm button on the app bar – apps from Microsoft and high-profile developers have adhered to the Windows 8 design principals. The one notable exception to this, of course, is the Bing app, for obvious reasons.

This week, however, two things happened. First, Microsoft released a series of updates for its productivity and entertainment apps. Many of the updates added support for type-to-search, which allows you to initiate a search by simply typing in your query from any screen. This, of course, was already supported in the Windows Store and on the Start screen. The Mail app, however, contains some interesting and potentially telling changes. Printers have always been directly accessible from the devices Charm, but a new print button on the app bar is essentially a shortcut to this menu with all non-printing devices removed. More importantly, a search button can now be found at the top of the email list. Like the print button, the search button simply launches the Search Charm.

Secondly, an early version of Windows Blue also leaked online over the weekend, revealing many of the exciting changes that Microsoft has in store for the first major update to Windows 8 and Windows RT. Strangely, the PC Settings “app” now includes a search box in the upper-right corner of the screen. Unlike the buttons in the new Mail app, Windows Blue’s PC Settings appears to eschew the Charms entirely, with search results appearing in a drop-down box. Windows Blue is still in development and subject to change, so the search box might not make it into the final build. But it’s still somewhat worrisome.

Based on these two recent Windows 8 developments, one has to wonder if Microsoft is going the Windows Phone route with the Windows 8 Charms. With more and more Microsoft apps adding search functionality to the UI, could the Charms be pushed into the background? It seems unlikely that Microsoft would remove them entirely, but why duplicate the functionality? And what will happen if the Search Charm is used for some apps while a dedicated search box is found in others?

The problem, of course, lies with the users, who seem to have trouble either finding the Charms or comprehending how they work. One could argue that this is a design flaw and that the Charms aren’t discoverable enough, but what about Windows Phone’s dedicated search button? It’s always right there in front of you at the bottom of the screen, yet it still proved to be too confusing for people. The problem, of course, is that we have been trained to look for a search button in the UI. In my own experience, it took me a few weeks to get used to using the Charms. But once I did, I quickly grew to love the context-sensitive functionality they provide.

Which do you prefer, dedicated in-app buttons or context-sensitive functionality built into the OS interface?