The HTC One M9 is about to be released in the U.S., as the first wave of 2015 smartphones begins to hit. But with fewer changes to design and specs than other Android flagship phones, the big question for prospective buyers is, What's really new or different about this year's HTC One?

To get a sense of what's changed and what hasn't, here's a rundown of the 2015 HTC One M9 compared to the 2014 HTC One M8.

HTC One M9 vs HTC One M8: Overview

Since its inception, the HTC One line of phones has always been about quality build materials, solid design, and hardware specs capable of keeping up with HTC's industry rivals, if not surpassing them.

This year's HTC One M9 keeps the high-quality design elements, including front-facing stereo speakers, metal and glass build materials, and an overall attractive, premium look and feel, all in a slightly smaller profile and (barely) lighter total package than the HTC One M8.

Like Apple's iPhone, HTC is sticking to what customers like: So far, so good.

HTC One M9 vs One M8 on Specs:

Display

When it comes to hardware updates, HTC's 2015 flagship is a little less impressive. It sports the same 5.0-inch Super LCD3 display, now with the latest Gorilla Glass 4 to protect against dings and scratches, and the exact same 1080 x 1920p resolution.

That resolution is still full HD, and there's still a debate as to whether better resolution is necessary for the general smartphone buyer.

But the Samsung Galaxy S6 now sports a 2K resolution, and with mobile VR headsets close to a general consumer launch, there appears to be a good reason for putting ultra HD displays on flagship smartphones -- if only to future-proof them for those applications down the road.

If mobile VR proves to be important, HTC comes up short with the One M9.

Speed, Power, and Storage

HTC has upped the 2015 One's RAM to 3GB, which is also the new standard for leading Android smartphones. But while the new Qualcomm Snapdragon 810 system on a chip is an improvement over last year's Snapdragon 801, it's still not a 64-bit processor (as Apple and Samsung now have).

On top of that, it appears the Snapdragon 810 is a bit of a disappointment as this year's incremental upgrade -- at least judging by Samsung's decision to drop Qualcomm from its 2015 flagship altogether.

Meanwhile, HTC appears to have upped the minimum internal storage to a standard of 32GB (over the M8's 16GB minimum), in keeping with the times. And HTC is one of the last holdouts to give consumers a microSD expansion slot (up to 128GB more), which earns the 2015 One M9 some extra credit, even if Android has been increasingly shunning microSD use since KitKat's release.

Camera

Fans of the HTC One M8's Duo camera -- the dual-sensor hardware that led to lots of fun Lytro-esq post-snap photo customization capabilities, as we reported in our hands-on review -- might be disappointed by the HTC One M9. The company decided to do away with duo.

However, HTC moved its low-light specialized UltraPixel sensor to the front (makes sense for indoor selfies without flash) and replaced the rear sensor with a 20.7-megapixel shooter. So the camera still counts as an upgrade, even if it's less unique than before.

Operating System and Software

Because we're comparing two phones from the same company, there's not a lot of differences to point out, except the obvious ones that come with a yearly update.

As such, while most HTC One M8 phones are either on Android 5.0 Lollipop or expected to get the update soon, the HTC One M9 will, of course, run Lollipop right out of the box. Along with the Lollipop OS upgrade comes HTC's latest Sense 7.0 UI customizations.

Sense 7 will give user more navigation control options, a broad swath of options to customize the look of icons, wallpapers, and homescreen widgets through a new app simply called "Themes," more photo-editing options and effects in HTC's camera app, and a new widget called Sense Home that lets you organize your most-used apps right where you need them, among other, more minor enhancements and additions.

The most important software upgrade, however, might be more contextual information in HTC's BlinkFeed screen. Like Google Now and other "smart" assistant software, BlinkFeed will now include personalized updates and recommendations based on the time of day, your location, and other clever ways of trying to gauge just what you want, just when you want it.

According to Android Central, HTC One M8 handsets are slated to get the Sense 7 update at some point, but the release date is still unknown. What is know is that they'll be second in line to the brand new M9, running the software package right out of the box.

Release Date, Availability, and Price

The major carriers like Sprint, AT&T, Verizon, and T-Mobile will all have the HTC One M9 in stock soon, along with retailers like Best Buy, and AT&T and Sprint already taking preorders online.

Pre-ordered HTC One M9 handsets are expected to begin shipping on Monday, March 30, 2015, with Verizon following up on April 1 to take preorders.

The base price, on-contract, of the HTC One M9 will run about $200, more or less (depending on trade-ins, special offers, and discounts). Without the subsidy, those looking to get an HTC One M9 can buy it directly from the company (since Friday, March 27) for $650.

But is the HTC One M9 enough of an upgrade to justify the price? Especially when the HTC One M8 is now selling for as low as $300 unlocked?

So far, it's hard to recommend it for anyone that's not a long-running HTC One fan who already intends to renew his or her contract and have already lined up the spending cash. It's just that not much different form the HTC One M8, and appears to be a little behind the curve of other 2015 premium phones (We'll always be open to changing our minds after a hands-on experience, though.)

Disagree? Tell us why in the comments, proud owners of the brand-new HTC One M9!