At the start I was, but now they have just been pouring them out and there is no way budget wise or time wise I can keep with all of it, also with all the other comics I am reading on a weekly basis.  Anybody been able to keep up with this stuff?

Yeah. There are quite a few, and there'll be even more with Uncanny X-Force, Deadpool, etc. tie-ins.
Best you can do is keep your regular pull-list and select a few tie-ins to read, because a lot of them aren't useful for the main storyline. Currently I'm following:
Fear Itself
Avengers ( always on my pull-list )
Invincible Iron Man ( always on my pull-list )
Fear Itself: Spider-Man ( ASM is always on my pull-list, so I felt I needed this one as well )
Fear Itself: The Deep ( added this one because it looked intriguing )
Fear Itself: Deadpool ( Deadpool is always on my pull-list, so I felt I needed this one as well - even though I'm fearing it will suck - ) 
Fear Itself: Uncanny X-Force ( UXF is always on my pull-list, so I felt I needed this one as well ) 
 
And I also bought the Fear Itself: Book of the Skull.

I can highly recommend Journey Into Mystery 622 and 623.  No epic battles or anything, but the storyline (Loki's plotting) is real good.

I also have the Iron Man tie ins and I think that's about it -- while I'm an issue behind reading Iron Man, it doesn't seem to really tie into much so far so if it's not on your normal pull list (it is for me), I'd pick something else up.

I can highly recommend Journey Into Mystery 622 and 623.  No epic battles or anything, but the storyline (Loki's plotting) is real good.

I also have the Iron Man tie ins and I think that's about it -- while I'm an issue behind reading Iron Man, it doesn't seem to really tie into much so far so if it's not on your normal pull list (it is for me), I'd pick something else up.

I'm getting Journey Into Mystery anyway and thoroughly enjoying it. It's just bled into Secret Avengers to which ive yet to read but I'm not having anything to do with this event mainly because I can't afford it and I did the whole event tie in thing with Siege which was occasionally worth it, I'l just pick up the trades one day I imagine.

Yes I am getting every single issue. Highlights so far have been all the Journey into Mystery issues, honestly? Best quality BUT, probably the least necessary as in plot details, as so far, that might change, but yeah. Quality of the story though? Incredible. Iron Man first issue tie in is meh, but second issue is huge! Very significant. War Machine 2.0 I mean... Iron Man 2.0 Tie in, is pretty decent. Worth it if your a fan of War Machine AND the Immortal Weapons. T-Bolts issues have been okay. Sort of half and half between their ongoing story and Fear Itself stuff.  The Defender Lite tie in was okay. Cosmic people might want to get it for a certain nude bald guy. 
 
Uhm. Any of you guys want me to do issue summaries of all issues in one thread sort of connecting everything up? 

No, tie ins drive me crackers. Even if someone gave me all the copies illegally on cd to read for nothing I wouldn't bother, even if some friend of mine went out and bought the comic issues for free and gave them to me as a present I wouldn't read them
 
Some comic characters/teams I just don't like so for me Tie ins are always a stupid idea 
 
I don't like New Avengers comics, Fan4 comics, or Hulk comics 
It doesn't matter what big arc or massive event Marvel management wants to tie these comicbooks into I'm just not reading them period