I'm not sure this is correct. You're assuming there are algorithmic changes to search that will substantially improve results to the point where the average user will notice - like there was when google made its rise.
At this point-barring some revolutionary new way to search-Microsoft might have to heavily invest in advertisements to gain any ground.
Indeed. 12 years ago, back when I juggled 4 or 5 different engines — I'd have welcomed something like Bing with open arms.
The thing is, in those 12 years, I've invested lots of data and time in Google. But be that as it may, I feel like I'm noticing a decline in the quality of Google search results. And there are rare occasions where I do give ol' Bing a few cranks to cover more bases.
At this point-barring some revolutionary new way to search-Microsoft might have to heavily invest in advertisements to gain any ground.