Rumor has it that Google is planning to announce a new version of Android in the second quarter of 2012, but that will likely leave a lot of Android users wondering, “Hey – what about Android 4.0?”

Google first announced its latest and greatest version of the Android mobile platform, code named Ice Cream Sandwich, back in October, and getting it onto existing smartphones and tablets has been a slow process. Now, it seems many devices in the Motorola camp may never get the update (or at least not anytime soon).

As Technolog reports, Motorola has announced that it’ll be bringing ICS updates to some of its devices by this summer, but many of its most popular smartphones and tablets have no set dates for upgrades. According to a post made by Motorola on its forums, only its Atrix and Photon smartphones are notched to get ICS updates, happening sometime in Q3 2012. As for its Xoom tablet, only the Wi-Fi based U.S. version has an ICS upgrade date.

In fact, the ICS update rollout has been slow-going for Android, which is the case with most upgrades to Google’s operating system. The trouble is that oft-cited Android fragmentation issue, which is exacerbated by the fact that there’s no real consistency between smartphones and tablets on different carriers and made by different companies. Each device using Android requires its own tweaks by that device’s manufacturer and by the carrier it uses, and that means that each individual device needs its own special brand of ICS before it can be upgraded.

The result is a staggering of updates that can take a long time to find their ways to end users, and despite all the very cool features Google touted in ICS back when it announced it, it’s mostly reserved for those Android users who were willing to purchase new devices like the Samsung Galaxy Nexus. Many device owners are still using version of Android that have been surpassed by one or two generations.

On the plus side, from the sounds of things, Android 5.0 isn’t Google jumping on to a new version of Android while its users languish with old versions of Android 2.2. Reports say that Android 5.0 Jelly Bean will be geared toward tablet PCs and is intended as a means for Google to compete with Windows 8 on those devices. If that’s the case, it’ll probably be more like Android 3.0 Honeycomb – a more niche software update that doesn’t affect most Android users.

ICS updates will continue to trickle down to at least some device owners, but one would think that with a new iPhone coming probably this summer, Google would want to kick its partners into gear to make sure Android users have the latest and greatest versions of the OS ready to go for as many people as possible. As it stands, though, it seems most users will probably be waiting quite a while for ICS, especially if they have Motorola phones.