Though it came out quite a while ago (May 2008), I have only just got round to analysing this amazing slot!
It quickly became a favourite of mine, so I just had to know more about it, specifically the odds of hitting the free-spins. So I have spent every spare minute of the last 2 weeks plotting the reel bands & working out the figures.

After just a few spins, all players will notice how reels 1,3 & 5 are full of one set of symbols, while 2 & 4 have a different set. But it's not until you see the actual layouts that you realise that the rare big symbols only occur ONCE on the other reels! These layouts mean the chances of hitting any wins are rare unless you have some stacked wilds in view.
But due to the distribution of the symbols, even getting a 5 stacked wilds on reel 1 or 3 does not guarantee you will get any wins - very frustrating when that happens! The slot has been deliberately designed like this to allow for the huge wins which you would get for multiple stacked wilds.
If I could chose which reels the stacked wilds would appear on I would ask for reel 2 first, then 4, 3, 1 & 5.

The Spin Graphics:
The reels spins, like many newer MG slots, are actually a graphic representation of all the symbols in the correct order. However, you may notice a 'jump' just before they stop spinning and maybe see only 1-4 wilds together even though you know there are 5 together per reel, or you may see 2 identical symbols next to each other. The reason for this is fairly obvious; the finishing position of each reel is determined by the RNG the instant you hit spin. The reels then start 'spinning', carrying on from the last position. The software then 'inserts' the finishing position for each reel (sometimes with a small overlap) just before it stops spinning.
e.g. Suppose the symbols were numbered 1 to 50 on a reel, and the RNG choose 5-9 to be displayed, you could see this in the spin:-
1 2 3 4 5 6 7 8 9 10 11 12 3 4 5 6 7 8 9
Where red is the 'cut in' for the finishing symbols, which are the bold ones.

What this means is you can not predict from the early part of the spin, what your final symbols might be.

The Nitty Gritty!
If you ever experienced a slow or disconnected internet you would see all the symbols on all the reels spinning round & round. This was how I first noticed that there are three scatter Cake symbols on reel 4 and two on reel 5 which was what made me decide to have a go at cracking this monster.
Reel 4 was the first one I plotted, and was a little, but not totally surprised to find it has 94 symbols. Reel 5 seemed to be in sync, so I knew that was the same. By observing the synchronicity to the other reels I guessed how many symbols they had too. This turned out to be wrong when I later discovered that reels 1 to 3 spin at slightly different speeds!

Finally I found these numbers of symbols per reel: 79, 74, 74, 94, 94.
Scatter Cakes per reel: 1, 1, 1, 3, 2
Therefore, odds of hitting a Cake on each reel = 1 in: 15.8, 14.8, 14.8, 6.27, 9.40

The Bottom Line:
Chances of getting 3 or more Cakes for free-spins: 1 in 160.42
Chances of getting the 'jackpot' of 5 wilds on all reels: 1 in 3,822,488,944
Yes, that's 1 in 3.822 BILLION!
However, you would obviously still get a very considerable win if you only got 3 or 4 wilds on some of the reels, or got 5 on only 4 of the reels (would give you 100 x 5 of-a-kind wins)
Chances of getting 1 or more wilds on all 5 reels: 1 in 64,734

To see all my stats and the actual reel band layouts, click here.

Despite the mind-boggling odds above, this is still a very good slot to play and turns out to have low-medium long-term variance provided you have the bankroll to play it at maximum lines. But be aware you can easily go for 10 - 20 spins hitting nothing (or very little), and that even getting the free-spins does not guarantee a good return. I've found it to be one of the most addictive slots I've ever played, so caution & control is advised.

Disclaimer: All of the above and the data on my site is based on my own observations, assumptions and calculations, so some of it could be wrong. (Not very likely! )