I use Meteor alot. Some of the issues mentioned here were about a lack of scalability in terms of larger sized apps and to the number of simultaneous users it

I use Meteor alot. Some of the issues mentioned here were about a lack of scalability in terms of larger sized apps and to the number of simultaneous users it can handle. If you have a large app you can use subscriptions that change as you view them. You can indeed have large 100,000 item collections without any hiccups or slowness. The issues people display here are if you have this 100k database downloaded on your browser which is unrealistic. The second as to scalability user-wise. It is possible to scale meteor by altering some code. Meteor's still a baby but their 1.0 release will definitely sort this out: The issues relate to how publish functions are handled & how mongodb interacts with meteor. These will be heavily optimized by running publish functions less & using a mongodb replica set emulated via meteor or through mongodb's oplog. I have built before with .NET (I hate it the most), Java, Rails, PHP, Coldfusion, you name it! One thing Meteor helps me do is build fast and expect something that works without bugs at the end. Its nice to experiment around with what people like till we get it right. I'm going to go so bold as to say Meteor will let people experiment with many ideas just as VCs do with ideas but here you can get that one which works without much cost & time to develop it. RoR is nice but when it comes to a funky front-end user experience its not nice. The backend is loads of fun!