Our previous rumour sources claim that the model will come in late May or early June and will be available in popular Black Mist or White Frost colours. It is also said to come in many SKU, including differences in dual SIM/single SIM configurations and antenna differences. There will probably a LTE version and a TD-SCDMA version for the China market as well.
Samsung Galaxy S4 mini will come with Android 4.2.2 Jelly Bean operating system and have a 4.3" 960x540 Super AMOLED display, a 1.6GHz dual-core processor and 1GB RAM. It will probably come in 8/16/32GB variants.