GW are releasing new paints again: http://www.games-workshop.com/gws/catalog/armySubUnitCats.jsp?catId=cat470002a&rootCatGameStyle=paints-tools


Interestingly, there seem to be new classifications/categories for each type of paint.

Citadel Base: Citadel Base paints are high quality acrylic paints specially formulated for basecoating your Citadel miniatures quickly and easily. They are designed to give a smooth matte finish over black or white undercoats with a single layer.
Citadel Shade: Citadel Shades are specially formulated to flow over other paints and into the recesses on your miniatures, defining details and accentuating recesses. Once applied, they dry to provide a very effective, matte shading for your models
Citadel Layer: Citadel Layer paints are high quality acrylic paints, and with 70 of them in the Citadel Paint range, you have a huge range of colours and tones to choose from when you paint your miniatures. They are designed to be used straight over Citadel Base paints (and each other) without any mixing. By using several layers you can create a rich, natural finish on your models that looks fantastic on the battlefield.
Citadel Dry: Citadel Dry Compounds are of a thicker consistency than other Citadel paints, which makes them perfect for drybrushing - a handy way to pick out the details on a model, or apply highlights swiftly and easily.
Citadel Glaze: Citadel Glazes can be used to intensify colour, allowing you to emphasise the strong colours on a model. With a similar consistency to a Shade, they provide a translucent layer across the colours beneath them that augments the original colour with a new hue. They are also useful for restoring colour to an area that might have been over-highlighted.
Citadel Texture: Citadel Texture paints are designed to provide a swift, effective solution to detailing your bases. They contain a mixture of both coarse and fine grit, which forms a rough, grainy surface that is ideal for drybrushing and ready for further detailing. They give strong, effective coverage over both black and white undercoats.
Citadel Technical: Looks like sort of an 'other' category. Contains Lahmian Medium (Lahmian Medium is a particularly useful paint when it comes to creating new colours. By mixing the colourless Medium with a Layer paint, you can create your own glazes to apply to your models, subtly altering the colour of a particular area. Lahmian Medium is also pretty handy for sealing a transfer to a miniature, providing a smooth matte finish.), 'Ardcoat (gloss varnish), Imperial Primer (undercoat) and Liquid Green Stuff (what it says on the tin...well...pot).

Official conversion chart
http://www.games-workshop.com/MEDIA_CustomProductCatalog/m2320032a_Citadel_Conversion_Chart