Not much, really

_{for now, at least}

From the blog post

How you use our site and our products will not change in the coming weeks or months, just as our company’s goals and strategic priorities remain the same. As the acquisition is finalized, and we continue to partner with Prosus, I will keep you all posted through my regular quarterly blog posts and Teresa Dietrich, our Chief Product and Technology Officer, will do the same in her quarterly community blog posts.

So, for the next couple month at least, nothing is changing.

However...

The blog post also said

Once this acquisition is complete, we will have more resources and support to grow our public platform and paid products, and we can accelerate our global impact tremendously. This might look like more rapid and robust international expansion, M&A opportunities, and deeper partnerships both on Stack Overflow and within Stack Overflow for Teams.

Which might mean more SE ads, and an influx of new users. Or it might mean something completely different, It’s difficult to tell.

Note: also see other answers, as this answer misses some things

Not much, really

_{for now, at least}

From the blog post

How you use our site and our products will not change in the coming weeks or months, just as our company’s goals and strategic priorities remain the same. As the acquisition is finalized, and we continue to partner with Prosus, I will keep you all posted through my regular quarterly blog posts and Teresa Dietrich, our Chief Product and Technology Officer, will do the same in her quarterly community blog posts.

So, for the next couple month at least, nothing is changing.

However...

The blog post also said

Once this acquisition is complete, we will have more resources and support to grow our public platform and paid products, and we can accelerate our global impact tremendously. This might look like more rapid and robust international expansion, M&A opportunities, and deeper partnerships both on Stack Overflow and within Stack Overflow for Teams.

Which might mean more SE ads, and an influx of new users. Or it might mean something completely different, It’s difficult to tell.

Not much, really

_{for now, at least}

From the blog post

How you use our site and our products will not change in the coming weeks or months, just as our company’s goals and strategic priorities remain the same. As the acquisition is finalized, and we continue to partner with Prosus, I will keep you all posted through my regular quarterly blog posts and Teresa Dietrich, our Chief Product and Technology Officer, will do the same in her quarterly community blog posts.

So, for the next couple month at least, nothing is changing.

However...

The blog post also said

Once this acquisition is complete, we will have more resources and support to grow our public platform and paid products, and we can accelerate our global impact tremendously. This might look like more rapid and robust international expansion, M&A opportunities, and deeper partnerships both on Stack Overflow and within Stack Overflow for Teams.

Which might mean more SE ads, and an influx of new users. Or it might mean something completely different, It’s difficult to tell.

Not much, really

_{for now, at least}

From the blog post

How you use our site and our products will not change in the coming weeks or months, just as our company’s goals and strategic priorities remain the same. As the acquisition is finalized, and we continue to partner with Prosus, I will keep you all posted through my regular quarterly blog posts and Teresa Dietrich, our Chief Product and Technology Officer, will do the same in her quarterly community blog posts.

So, for the next couple month at least, nothing is changing.

However...

The blog post also said

Once this acquisition is complete, we will have more resources and support to grow our public platform and paid products, and we can accelerate our global impact tremendously. This might look like more rapid and robust international expansion, M&A opportunities, and deeper partnerships both on Stack Overflow and within Stack Overflow for Teams.

Which might mean more SE ads, and an influx of new users. Or it might mean something completely different, It’s difficult to tell.

Note: also see other answers, as this answer misses some things