Just about all of the hype around Microsoft's Surface tablet lineup revolves around the forthcoming Surface Pro 5. And for good reason: The current-generation Surface Pro 4 is a dynamite device -- one of our favorites -- that combines power, portability, and productivity in just the right way. After its October 2015 introduction, the Surface Pro 4 instantly became the standard-bearer for Windows tablets. It's both a unique alternative and worthy rival to Apple's iPad.

But the Surface Pro isn't the only Surface tablet in Microsoft's portfolio. There is also the less expensive non-Pro variation, the most recent of which is the Surface 3. And based on the rumors, it appears that Microsoft may introduce a new version of this second-fiddle model -- the Surface 4, presumably -- at an upcoming event in New York City on May 2.

In the current tablet market, which includes recent standouts including Google's Pixel C, Samsung's Galaxy Tab S3, and Apple's newest and least expensive iPad (the $329 9.7-inch model, introduced in March 2017), the Surface 3 doesn't look like much. Initially priced at $499 -- which (inexcusably) did not include the essential $129 keyboard/cover -- the well-designed Surface 3 did correct some of its predecessor's flaws by integrating a full version of Windows for the first time and delivering more processing power.

But when Microsoft followed up seven months later with the Surface Pro 4, it was pretty much curtains for the Surface 3. After cutting the price to $399, the company discontinued the overshadowed Surface 3 at the end of 2016. Now, however, it seems as though the company may be preparing its successor for the light of day. More on that below.

And what about the Surface Pro 5? Yeah, we may be waiting for that one a little while longer. In the meantime, check out the Surface 4 rumors to find out what Microsoft may introduce soon and what it may leave in reserve for the Surface Pro 5's debut, expected to come later this year.

Announcement and release

The most solid rumors about the Surface 4 relate to timing. According to sources, Microsoft will debut the new tablet at its event scheduled for May 2 in New York City. It's less clear whether the new device will be immediately available for purchase, but probably not: Microsoft has typically allowed a month or so to lapse between Surface product announcement and release.

Under the hood

Despite all the buzz surrounding the Surface Pro 5, there hasn't been much speculation about Surface 4 specs. And it's tricky to make predictions about this product. As Mary Jo Foley at ZDNet points out, Microsoft uses the Surface portfolio primarily to create new product categories -- it doesn't want to compete with partners such as Acer and Lenovo in existing categories.

Given this, it would be awkward for Microsoft to simply give the Surface 3 a makeover -- outfitting it with components that are newer but still inferior to those we expect to see on the Surface Pro 5. So, it's reasonable to expect to see some new features and capabilities with the Surface 4.

Software is one area of high potential. On April 11, Microsoft released a major update to Windows 10 (learn how to access the free download here). Creators Update includes new 3D apps, VR capabilities, enhancements for gaming, and enterprise security features. The new Surface 4 could leverage some of these new capabilities.

Or, according to another theory floated by Mary Jo Foley, Microsoft could debut a Surface 4 that runs the rumored Windows Cloud operating system which is reported to limit users to apps installed through the Windows Store. This kind of walled environment could make sense in an educational context -- which brings us back to the announced educational focus of the May 2 event. We'll see.

Otherwise, the hearsay cobbled together from Reddit forums and other unreliable corners of the Internet posit that the Surface 4 could follow the Surface Pro 4 by omitting the home button and using a side-attaching stylus. Or it come come equipped with a USB-C port, more kickstand positions, and an updated Intel processor. And in the long-shot category, there is Microsoft's patent for a hinged display (unearthed and published on Twitter by WalkingCat). But it's highly unlikely we'd see this kind of boundary-pushing feature debut on the Surface 4.

Price

This is where things get really interesting. With Apple dropping the price of its newest iPad, and a growing array of excellent, inexpensive midrange tablets on the market, there is tremendous pressure on Microsoft to price the Surface 4 more aggressively than previous editions. The Surface 3 debuted at $499 -- plus an additional $130 to get the keyboard -- before dropping to $399. Unless Microsoft takes a totally new, way more premium tack with the Surface's hardware and design, that kind of price tag simply won't fly in 2017.

Scroll down for a reverse-chronological look at the latest rumors.

April 12, 2017

ZDNet: Microsoft sets May 2 for (Surface-less) New York event

The company will hold an event in New York featuring CEO Satya Nadella, but don't expect to get a glimpse of the new Surface Pro tablet.

April 11, 2017

ZDNet: Microsoft's rumored Spring event may focus around Windows 10 Cloud

The still-unofficially-announced Windows Cloud edition may be the focal point for Microsoft's Spring launch event, which sources say looks to be happening in early May.

March 27, 2017

ZDNet: Microsoft's Spring fling: is another new Surface device category coming?

Microsoft's anticipated Spring hardware launch is unlikely to feature the Surface Book 2. So what else might be on the docket?