For 6-12 months
(This could also be added to a registry!)
At 6-9 months, baby will be into grasping things, so supply plenty of different textures, and toys with direct feedback. And chewing! Here are some sure-to-be favorites:
Soft blocks (we didn't have these exact ones, but something very similar...)
Baby Einstein - Buttons make music! Every kid has this. It is awesome. For us it was a car toy, and easy way to entertain him for at least 10 minutes.
Stacking cups - any generic set that also has holes in the bottom, which is also great for use in the bath. And fun for kid and parent are these Tobbles stackers.
Things to encourage movement and crawling...so anything that moves. Add a cause/effect action if you can, like this Inchworm does. (This one is more foolproof than ones that require buttons.) Or toys that wobble are also good. Anything that makes them track and reach.
Plastic keys, plastic rings, rattles on rings, little mirrors, etc. - small, lightweight stuff she can easily hold.
And the same thing but in larger form that you can prop on her lap. Lamaze makes great stuff. We have the robot, but they are all neat.
Toys they can sit up at go over well too - like this little piano. (And this makes for great photo ops!)
The other thing is you might want to ask for things to childproof your house - cabinet latches and things. Because she'll be pulling herself up and maybe crawling in the next 6 months and you don't want whatever it is to crash down on her.
Generally, speaking -
Exersaucers and the like are horrible from an occupational therapist perspective. Babies need to move. It is how their brain works. It is why they like us to carry them - because they are moving. And forcing a baby into a position that they cannot hold on their own (sitting when they don't actually have the stability, standing when they don't have the strength) can trick their brain into them thinking they already have the skill, and can further delay them. 2 quick articles:
Therapists Weigh-in on Bumbo Seats - from the Chicago Tribune
Information from Physical Therapist specializing in Pediatrics