What is the most abundant protein in humans? ...on earth?

Today at lunch we had a heated discussion on what is the most abundent protein in humans (by mass?). We speculated that it would be a member of the cytoskeleton (actin, keratin), or part of blood (albumin, hemoglobin), an extracellular matrix/bone component (collagen), a mithochondrial enzyme (GAPDH), a very small abundant protein (ubiquitin), or a component of chromatin (histones). We each picked one and made a bet to what google would tell us. Well after a bit of searching here is what I find. From google answers: "I have found definite statements that collagen is the most abundant, followed by actin. I have found claims that osteocalcin takes the 7th place, and SOD the 5th. Albumin, myosin, keratin and the globulins are also strong contenders for places in the top 10."
There is of course differences when you compare moles and mass, as proteins like collagen are massive (>1000AA) compared to something like ubiquitin (<100AA). But looking at mass we can guess something like this...

1. Collagen (25% of proteins)
2. Actin (20% of dry muscle mass)
3. Myosin? (second most abundent in muscle) or keratin (most abundent in epithelium/hair)?
   
4. Albumin? (60% of serum protein,and only 40% of all albumin is present in serum)
5. Superoxyde dismutase (most abundent in mitochondria)
   
6. Hemoglobin? (95% of RBC dry mass)
   
7. Osteocalcin (second most abundent in bones after collagen)

But which protein is most abundant on earth? Well it turns out it could be rubisco, the photosynthesis enzyme (30-50% of soluable chloroplast protein), found in plants, algea and plancton...
However, I have not given up on the idea that it should be a bacterial protein considering they have so much biomass, all to way to 2km down the crust and at the bottom of oceans. I would quote Stephen J Gould for this matter : "When one considers how deeply entrenched has been the dogma that most earthly biomass lies in the wood of our trees, this potentially greater weight of underground bacteria represents a major revision of conventional biology and quite a boost for the modal bacter. Not only does the Earth contain more bacterial organisms than all others combined (scarcely surprising, given their minimal size and mass); not only do bacteria live in more places and work in a greater variety of metabolic ways; not only did bacteria alone constitute the first half of life's history, with no slackening in diversity thereafter; but also, and most surprisingly, total bacterial biomass (even at such minimal weight per cell) may exceed all the rest of life combined, even forest trees, once we include the subterranean populations as well."