http://knstrct.com/ - General design blog, but often heavy on interiors and architecture
Architizer Journal: The Official Architizer Blog - Huge architectural design project database
http://www.weheart.co.uk/ - Again, general design blog, but very nice interiors and archicture - out of the UK
http://www.thecoolhunter.co.uk/ - Similar in concept to weheart, but with different content - also out of the UK