Now that Microsoft's Surface Pro 3 has settled in to its release from earlier this year, many are already hearing rumors of what will come with the next iteration: the Surface Pro 4.

When the Surface Pro 3 released in June, the new Microsoft tablet brought about a few changes from the Surface Pro 2, namely a larger 12-inch screen, lighter weight and the edition of Windows 8.1 Pro, but many fans are wondering if the biggest changes were being saved for the Surface Pro 4.

Many are speculating that the Pro 4 could stretch up to 14 inches as the bigger-is-better trend continues into the new year. But it's the improved processor that is almost a certain addition.

Not long after the Surface Pro 3 was released, Intel showed off its new and improved Core M processors that works without the traditional cooling fans, allowing even further portability and space-saving design. It's the release of the Core M that has many excited about its possible inclusion in the Surface Pro 4.

But perhaps most rumored to be included with the Surface Pro 4 is Windows 10. After all, the whole reason consumers turn to the larger laptop-style computers over mobile tablets is the availability of the desktop operating system over the streamlined mobile operating system.

Windows 10 is currently available as a technical preview to Windows Insider program members, but not yet to the general public. This allows more advanced users to take a look at the pre-release build to gather feedback throughout the development process.

But the retail release of Windows 10 is not expected until "late 2015," according to rumors. The question is, will Microsoft wait on the Surface Pro 4 to be released with Windows 10, or will it release several months earlier with Windows 8, and the option to upgrade to Windows 10 upon release?

"Some have speculated that Microsoft will likely unveil the Surface Pro 4 alongside Windows 10, coinciding with its release date," Android Origin reports. "On top of that, the Surface Pro 4 may very well be one of the first devices that comes straight out of the box running this latest Windows update. Windows 10 is speculated to be launching at some point in late 2015, so we'll probably have to wait almost another year to see the next addition to the Surface range, but it should be well worth the wait."

Another big question for Windows 10 is price. Will it release as a free upgrade for Windows 8 users, or be charged an additional fee because of all the new features it brings? 

And don't forget that blog post from Microsoft stating that all Surface Pro 3 accessories will "carry over." Brian Hall, General Manager for the Surface Line said in the post, "We are pleased to share that the following Surface Pro 3 accessories are designed with our product roadmap in mind and will be compatible with the next generation of the 'Pro' line Surface."

So with this post, the rumors about a beefier mobile processor, and the Windows 10 release date spculation, it looks like the Surface Pro 4 will not only be the best Surface Pro to date, but we may have to wait another year before we can get our hands on it.