The Verite influence map is probably the most widely viewed image in the EVE community, tracking sovereignty gain and loss in nullsec. The overlays give players a tangible tool for viewing the size and influence of alliances and coalition. Though it's sometimes inaccurate, it's possible to save the daily sov map for weeks or months and watch the colors spread, retreat and intertwine.
What the map doesn't do is show an overlay for coalitions and blue lists. The entire northwest portion of the Sov Map, for example, is controlled by a single coalition, as is the entire southwest and northeast. The southeast is a mess of alliances and coalitions attempting to attack or defend holdings, and though -A- is shown to hold several regions, they are virtually undefended and in the process of being steamrolled by several potential sov holders at the moment. Verite's map also doesn't show residents of NPC regions or non-sovholders. Pandemic Legion is one of the biggest alliances in terms of supercapital numbers at the moment, but holds no sovereignty. My alliance, Black Legion, lives in NPC Venal but likewise does not appear.
The takeaway is that it's difficult to estimate how powerful an alliance is based solely on the sov map. Owning sov does not mean you're capable of holding it, and owning no sov doesn't mean you're incapable of taking it. Pandemic Legion could certainly take and hold an entire region if they so wished, but this would make them less capable of deploying in distant regions. But by keeping track of the news and forums, one begins to understand the strength of particular powerblocs and, if engaged against one another, who will cascade.
The myth perpetuated on sites like EveNews24 and the EVE-O forums is that the CFC and HBC are working in tandem to take over the entire sov map. This is not entirely true.
I use that caveat - entirely - because there is a non-zero possibility that the HBC and CFC could either push out or include in their respective coalitions every conquerable 0.0 region in New Eden. Should the cards fall into place in just the right way, should diplomats and leadership enforce neutrality without failure, should the respective coalitions respect this neutrality enough to spark few if any diplomatic incidents, and should entities still exist - sov-holding or not - which can provide the occasional 'goodfites', perhaps over moons or other strategic objectives, outside of the CFC and HBC, then we might be a Sov Map entirely dominated by alliances blue to either the CFC or HBC.
That contingency is, however, both incredibly unlikely and not worth worrying about.
The first reason that this is unlikely is that projection of power becomes prohibitively difficult beyond a certain point. Posters on EVE-O have been arguing for years that alliances should be penalized for holding sov beyond a certain number of systems. In theory, this would limit the ability of coalitions to project power. In practice, holding many regions would be as difficult as forming new alliances to hold them, but more importantly, there are other factors preventing coalitions from growing to a certain point. Frederick the Great once said he who defends everything defends nothing, which has been proven true for all previous mega-powerblocs in EVE: Band of Brothers, IT Alliance, Northern Coalition and the Drone Russian Federation all fell under the weight of their own dysfunctional power structures. With a lack of real enemies came a lapse in discipline and FC experience. Coalitions which aim to reduce their risk by eliminating threats end up losing the players who play EVE to fight. These players eventually become the undoing of the coalition.
The second reason this is unlikely is because, unlike previous powerblocs, the CFC and HBC understand the importance of having real enemies. They could certainly push through and dominate the eastern sov map. They could do it together or separately. They could do it without blues living in the region. And they could do it regardless of whether or not the entire eastern sov map decides to blue up as one massive Anti-BadgerFuck Coalition (I hold all rights to this name, by the way). But what they would rather do is have non-HBC/CFC entities living, growing and fighting in an uncontrolled region of the sov map that can provide a real threat, either constantly or in relatively frequent regional conflicts. What this provides is the context for the respective coalitions to remain together, because otherwise, the only thing left to fight is blue.
And the reason why this contingency isn't even worth worrying about, should it come to pass that the HBC and CFC control the entire sov map, is that it would guarantee an HBC vs. CFC war. Whether or not this war is "sanctioned" (think of the never-ending war between Red Federation and Blue Republic of RvB) is irrelevant; belonging to either the HBC or CFC would still enable you to fight in large-scale fleets, small gangs or solo. What would be the difference between this and the current 0.0 situation? If you wanted your alliance to be aligned with nobody, NPC regions will certainly provide. Would there still be a Tech cartel? Absolutely, but the recent alchemy changes ensures that Cobalt forms a ceiling above which Technetium cannot climb.
In short, it's time to stop worrying so much and learn to love the NAPfest.