The biggest shift currently occurring in the software development world is the shift towards application stores and marketplaces. Everyone knows that mobile is currently the new frontier in computing, and we are rapidly moving towards a world where mobile smartphones/tablets outnumber desktop computers. Portable devices will be what everyone is using for everything in 10 years (I believe they will also have the modularity to take on desktop-like qualities when at a "base station" for additional power and bandwidth, but that's a separate thought). This means that the trends and occurrences in mobile will matter greatly, not only on their own, but I also believe these trends are going to make their way back to the desktop and recombine and continue to grow and evolve.
Prediction One: Chrome Web Store supports Android
In short, this means that all of the web applications currently in the chrome web store will become available on Android. This would mean that a company (Flixster for example) could develop an application using HTML that works on desktop computers as well as on mobile. Users could then visit this "application" or website using their computer, or they could install it on the Android phone, and the application would get instant access to location-awareness, notification support, and local storage.
Google will need to make this move quickly to secure their position as Mobile leader, so I see them announcing this technology at Google IO 2011, which should be happening in May. If they can launch this technology, and quickly follow up with Android 3.0 with full support, this technology should be widespread by 2012. The biggest problem Google and Android are running into is an inability to get manufacturers and carriers to release newer versions of the Android operating system quickly enough. This is evidenced by my phone (which is arguably one of the most advanced Android hardware sets), the Samsung Vibrant, is still only running Android 2.1 (Eclair).
Prediction Two: Windows Live Marketplace for Desktop
In general, Microsoft is great at identifying good technologies, and attempting to recreate them as Microsoft technologies. Microsoft's only entrant into the app store world is currently for their Windows Phone 7, but this will change as the shift to app stores continues. Unix/Linux users have long benefited from a central repository of software (apt repostiories for Debian / Ubuntu, Portage for FreeBSD / Gentoo, yast for Red Hat, pacman for Arch, etc); Microsoft is going to want to capitalize on the capabilities and benefits of these types of systems
I see them launching this at some point in late 2011 or 2012, probably coinciding with the next version of Windows, whenever that is finally released. Microsoft is slow to catch on to trends like this, but that's something they are always looking to improve and expedite, so we will see how quickly they can capitalize on this idea.