There is some chatter around now that there is an official price jump coming for several items from Games Workshop on June 1st. This seems to effect mostly paints, hobby tools, and some scenery kits.
While I have not seen an official list or notice, here is where the information is coming from.
http://www.gamingfigures.com/
via Gamingfigures. There are more details on their site.
As of the 1st June 2015 several of their ranges (mainly hobby/paint ranges) will be going up in price.
The RRP on paints will be increasing to £2.55 (currently £2.40). Chaos Black, Skull White and Purity Seal sprays will be increasing to £10.40 per tin (currently £9.80).
The price increase will also affect the Tools, glue and other modelling supplies.
The Aegis Defence Line scenery kits is increasing to £22.50 and both Realm of Battle boards are increasing (Sector Imperialis up to £220.00 and the standard board up to £200.00).