The redevelopment of Tottenham Court Road Underground Station will probably become a recurring theme over the coming months. Possibly years (groans to self). Blame Crossrail, not me.
Therer are a number of reasons for this:
1) The planned size and impact of the works are huge.
2) TCR is the closest tube station to where I currently work.
The recent permanent closure of Andrew Borde Street has had the effect of diverting a number of bus routes in the area, closing some bus stops and (I think) adding an additional stop or two on Shaftesbury Avenue.
I tend to use the Central or Northern Lines when in the area, or I walk. I rarely use the buses around Tottenham Court Road, so do not feel suitably qualified to offer a blow by blow account on the changes to the various bus routes in the area.
Details of current and future changes to London bus routes are available here. A spider map is also available here, though personally I find that this style of map is less useful when focused on the target spot.
As some of the changes will either be permanent, or will last seven years, you'll have plenty of time to get used to them!