Beat (not complete) this the other day, thoughts below:
+Looks great. Really, really good gfx considering the scale of the game, in particular indoor environments look better the previous games in the series
+Decent performance considering the above. I played on a 3670k/7950 setup and it generally ran pretty well
+Heists are generally good fun
+Not many weaknesses in terms of the different facets to the game i.e. driving, on foot, minigames etc are all generally done fairly well
+FPS view! Although I didn't use it that much
+Some really fun side missions like when you first meet Dom
+Usual funny dialog etc as you'd expect from GTA series
+Interesting twist with the 3 characters etc which makes a few of the missions more fun as well being able to switch away to a sniper or whatever
-Difficult to build empathy with the characters in the early part of the game as your time with them is fragmented.
-Story a bit difficult to follow at times (probably due to jumping around between mission/character types)
-Races kinda suck - doesn't feel like they have moved on much in the past 10 years, and also rendered far too easy by Franklin's special ability
-Felt like there should have been a couple of extra heists or otherwise making more use of the NPC team members
Overall I would probably rank this as my favourite in the series. Vice City is arguably a better setting but I think it would show its age now in terms of graphics and game mechanics.
+Looks great. Really, really good gfx considering the scale of the game, in particular indoor environments look better the previous games in the series
+Decent performance considering the above. I played on a 3670k/7950 setup and it generally ran pretty well
+Heists are generally good fun
+Not many weaknesses in terms of the different facets to the game i.e. driving, on foot, minigames etc are all generally done fairly well
+FPS view! Although I didn't use it that much
+Some really fun side missions like when you first meet Dom
+Usual funny dialog etc as you'd expect from GTA series
+Interesting twist with the 3 characters etc which makes a few of the missions more fun as well being able to switch away to a sniper or whatever
-Difficult to build empathy with the characters in the early part of the game as your time with them is fragmented.
-Story a bit difficult to follow at times (probably due to jumping around between mission/character types)
-Races kinda suck - doesn't feel like they have moved on much in the past 10 years, and also rendered far too easy by Franklin's special ability
-Felt like there should have been a couple of extra heists or otherwise making more use of the NPC team members
Overall I would probably rank this as my favourite in the series. Vice City is arguably a better setting but I think it would show its age now in terms of graphics and game mechanics.
and I agree, quite surprising how we have almost 500 crew members but I see about 10 online regularly. (may be easier to add as friends for some) 
