Alright I'm about 14 hours in and I can confirm that the dialogue does get better. Through the first few hours I was getting a little worried. The introduction is not too good, it feels rushed with bad dialogue, and the next two missions don't get much
better. They only give you two dialogue options in situations where you should have more. I felt the first 4 hours just kinda seemed like a Micheal Bay movie and I was getting a little worried that Mass Effect 3 was gonna end up like gears of war. But
DO NOT PANIC the dialogue does in fact get much better particularly after you start to recruit crew members.
After the first initial missions and after you get to explore the Citadel and start some side missions the game starts to feel like good ole Mass Effect again. The weapon customization and upgrade system is awesome, feels alot like ME1. I think they did a good job again at polishing the combat and cover system, and the skill point system is definitely better than ME2, but still not amazing. Most of the technical things they changed/added I really cannot complain about.
Overall I think they did a great job at combining the good parts of ME1 and ME2. You have to take the game for what it is, and its really good. It may not be your typical in-depth, spreadsheet type RPG, but so far I am liking this better than ME2 and am really enjoying it. It is definitely a quality game you just have to let go of your strict definitions of Shooter and RPG and just enjoy the last episode of a trilogy that the gaming community won't soon forget.