If this isn't weather-related (doubt it, mine warms up at the same rate cold or hot), It's either a stuck open t'stat, bubble in the system or a sending unit problem. Your plan of attack covers 2 of 3. Check the sending unit while you are in there to cover all bases.
__________________

2004 Dark Plum Base with windows tinted, cabin filter, silencers removed, fog lights, 18\'s, all Red taillights, Blaine\'s struts, modesty cover, color-matched center dash, 06 rear bumper
|