MAASAI  MARA

It's a surreal feeling to see Lions, Elephants, and 10,000 strong herds of Wildebeest, look around and see no fences, and no it's just you and the animals.  It's a bit of a bumpy and dirty ride out to the Maasai Mara but once the dust clears and you begin to see animals all your mind can focus on is the wonderful current moment.  This park has always been renowned but it certainly increased in recently popularity due to the fame of the BBC's Big Cat Diary that tracked a few Lion Prides and individual Cheetahs and Leopards.  There's prides of lions everywhere so there is no need to focus on retracing the steps of that film crew.  We spent two full days driving around the park and other than a Leopard and a Rhinoceros saw every other type of animal we wanted.
Supposedly the Maasai Mara has the largest and highest concentration of Lions in Africa.  With the annual Wildebeest Migration there's not too much wandering the Mara Lions need to do in order to find a meal.  I think an argument could be made to visit the part while the wildebeest migration is NOT happening because it may mean that the lions are more active. Lions tend to hunt and feed at night, then rest during the day. If it's easier for them to hunt, they may head back to their den earlier in the morning. I estimate that we saw at least thirty lions but only one set of cubs.
Not only does the Mara have the highest concentration of lions but supposedly also the largest lions. We had two South Africans stay in our camp one night. They'd been to the Okavango Delta as well as just about every safari park in South Africa and they said that the Mara lions were the largest they had ever seen.
A couple of giraffes hanging out.
A herd of cape buffalo. Buffalo was a component of seven of our nine dinners. It went from being an exotic meat to dreading our next meal. We did not see too many hyenas but they were probably the creepiest animal we saw. They are an ungraceful dog/cat combination and appear much larger in person than they appear in photos. 
Speaking of ungraceful animals. Wildebeest are a strange, gangly look cow/deer animal that roam in herds of up to a million. If you see one, you'll see a hundred thousand. One of their oddest features is how disorganized and random their movements seem until the begin to walk from one grazing area to another. At that point, they line up in single file rows and march behind one-another.
There's an ostrich couple and a serval.
The Mara has its fair share of elephants. It was elephants that gave the Mara its look and feel. The term Masai Mara refers to a landscape that is blank except for a few random trees that appear as dots on the horizon. It was the elephants that marched around, clearing the land, and knocking down trees that over millions of years created the great plains of the Mara.
We did not see any leopards or rhinoceros on our safari but we did catch a glimpse of this resting cheetah. 
We saw a group of wildebeest run through the river at a low point. Below are crocodiles and another point in the river where the wildebeests were not so lucky. Our safari van is the bottom right photo.
Hippos are supposedly the nastiest animals. We kept our distance.
We saw a bunch of zebra.
On the drive out of the park we saw four male lions together - which was a good highlight to leave the park.
Here's the leader of the four lions wondering off to do his thing.
There was a small herd of giraffes near the gate.

MAASAI MARA LIONS

I estimate we saw around forty lions during our time in the Maasai Mara but the highlight came when we saw a group of four male lions on our exit drive.  It's not uncommon for two male lions to team up after being booted from the pride, however, it was pretty special to see two groups of two team up and then have all the lions pass within a few feet of you.

WILDEBEEST MIGRATION

As impressive as the lions were the sheer volume and behavior of the Wildebeests may have been the most lasting image.  I enjoyed popping the top of the van and standing up as we drove through 10,000 strong herds of Wildebeest.  You'd see one, then fifty, then scan the horizon and there'd be 10,000 more. 

There's about 1.5 million Wildebeest in total and every year they follow are circular migration that starts in the Serengeti, cross the Mara River into Kenya, then eventually head south again to Tanzania. 

MAASAI MARA - OTHER ANIMALS

There are animals of all kinds in the Maasai Mara.

The park itself is also distinct for the open plains and one off trees - Mara loosely translates as "spotted" in reference to the trees.  Even in the instances when you don't see any animals the natural scenery and clouds over head still make for an enjoyable viewing experience.

HIPPOS AND GIRAFFES

The Maasai Mara has several large hippo pools.  You can get out and walk around these areas but be careful as hippos are responsible for the most amount of human casualties of people on safari.

Giraffes seemed to be the most curious animals we saw on safari and would tend to linger around vehicles and in some cases seemed to even pose for pictures.  Lions and other animals seemed almost oblivious to our presence and the Wildebeest were too schizophrenic to make any sort of conclusion.

MARA ELEPHANTS

While giraffes may have been more curious, elephants seemed to more acknowledge your presence - I swear an elephant used it's trunk to wave to us - at about the 1:50 time spot in the clip.

The Mara Elephants were interesting but they hardly compare to the volumes in Amboseli.  I wouldn't necessarily wait for an elephant to "cooperate" for the perfect photo if you are heading to Amboseli later in your trip as there are more opportunities in that park. 

EAST AFRICA BIRDS

The large animals are the highlight but there's also a lot of unique bird life in the parks as well.  There's also quite a few unusual trees and plant life which seemed to impress my parents (Pete, Diana, and me a little less).
For additional photos see the Maasai Mara Flickr Album.