I'm a bit lost. After House of M and Decimation, what is the order for all of the X-Universe stories? I know that things like Utopia and Dark Reign and so on have to fit in somewhere but I just can't make heads or tails of it. Could someone provide assistance?
 
Cheers

Hmmm, quite a lot of reading involved here if you want to get right up to date. The following list is in roughly chronological order for the trade paperbacks current out there, though bear in mind that some stories overlap or run at the same time (especially the Cable, X-Force and Legacy stuff between Messiah Complex and Second Coming). 

X-Men: Deadly Genesis 
Uncanny X-Men: Rise and Fall  of the Shi'ar Empire 
X-Men: Supernovas 
X-Men: Blinded By the Light 
X-Men: Endangered Species  
X-Men: Messiah Complex 
Wolverine: Get Mystique 
Uncanny X-Men: Divided We Stand 
X-Men Legacy: Divided He Stands 
X-Men Legacy: Sins of the Father 
X-Men: Original Sin 
X-Men Legacy: Salvage 
X-Force: Angels & Demons 
X-Force: Old Ghosts 
X-Force / Cable: Messiah War 
X-Force: Not Forgotten 
Cable: Messiah War 
Cable: Waiting for the End of the World 
Cable: Homecoming 
Uncanny X-Men: Manifest Destiny 
Uncanny X-Men: Lovelorn 
Uncanny X-Men: Sisterhood 
Dark Avengers/Uncanny X-Men: Utopia 
Uncanny X-Men: Utopia 
X-Men: Necrosha 
X-Men: Second Coming 
X-Men: Second Coming - Revelations 
Uncanny X-Men: The Birth of Generation Hope 
Uncanny X-Men: Quarantine 
Uncanny X-Men: Breaking Point 
Generation Hope: The Future is a Four Letter Word  
Think that basically gets you up to date with the current monthlies and what's going on with Fear Itself and Schism. Ones in bold are the essentials of the list, plot-wise (in my opinion anyway!), with the X-Force/Cable stuff running a very close second. 
 
There's some great stuff in there. The X-Force stuff, Deadly Genesis, Shi'ar Empire, Legacy and Second Coming storylines are awesome. Necrosha and the Dark Avengers cross-overs are probably the weakest.  
 
Good luck and enjoy! 

Meant to say that Civil War happens before Messiah Complex but the X-Men tie-in is pretty average and goes nowhere. Not read the wolverine tie-in though, so that may be worth a look. Also, Secret Invasion happens around about the Uncanny X-Men Manifest Destiny/Lovelorn stuff I think. Again, not read this so don't know what it's like. Finally, The Dark Avengers cross-over is pretty much smack bang in the middle of all the Dark Reign goings on near as I can tell.