There are several distinct types of 40k blog in the 40k blogiverse aren't there?
There is Faeit 212 a rumour site giving advanced news of what GW is planning.
There is From The Warp a mainly tutorial site focused on painting. If you want to learn something about painting this is the place to go. Then there is BOLs. editorials, tutorials, mini dexes, several forums. Its the one site that has everything. Then there are the personal journeys through the 40k hobby. What niche does your blog fit into?