Apple - Will the new 2015 "MacBook" be able to run VMs effectively? Windows especially

As far as I know, the new MacBooks as of today have only begun shipping from online orders, so I won't be able to speak from personal experience - but I would be very wary about the MacBook being able to handle intensive tasks like Parallels, especially in tandem with Visual Studio or Eclipse.

Parallels' recommended hardware specs for running Windows 7 include "...an Intel Core 2 Duo, Core i3, Core i5, Core i7, or Xeon processor (Core Solo and Core Duo processors are no longer supported)." The new MacBook has sufficient RAM (8 GB minimum) to fulfill their requirements, but the Core M processor (see the tech specs) will be the issue with running these types of tasks on the MacBook.

Check out the benchmark details here compared to the i7 that you are using currently and you'll see a noticeable difference - Core M running at 1.1GHz which effectively makes it a mobile processor if anything.

The machine is slower than a MacBook Air, but definitely capable of running VMs (I remember running VMs on the first generation Intel MacBook - which was never an issue).

Try monitoring CPU usage on your Air to get an idea of how much load you put on your system. If it's frequently on the edge you probably won't be happy with the 12" MacBook. If it's in the lower percentages usually, it should work quite well.

Keep in mind that the MacBook is only available with 8GB of RAM. So if you frequently have issues with RAM usage now, you'll see a lot more of those errors..

It runs parallels absolutely fine, I use it to run autodesk design review on external monitor whilst having Mac running excel on macbook screen, no issues and very pleased that it can do it as well as my 16Gb Ram quad core MBPro.