Boards and bits has Monty Python Fluxx for $2 cheaper than even that discount provides. Is this a new printing with something extra or different that LL is offering?
It's the same printing of Monty Python Fluxx, but Fluxx 4.0 and Pink Treehouse are brand new items that probably have not made it to most mail-order places yet. Follow the links above for more details.
This offer is for $5 off any one order you make, no matter what it is (if you're a new customer). You can get some Looney Labs stuff cheaper than $5 off elsewhere, but I'm sure you can stuff from them directly that noone else discounts, such as the more obscure titles or accessories. For example, you could order several promotional cards for Fluxx or Chrononauts -- typically $1-2 each -- and get a discount off of the total.