Depends what you are looking for. For an office box (read: stability over options, simple builds used for simple tasks), then the following list applies:
1. Intel over all others (for an Intel build obviously)
2. ASUS/Foxconn/ECS (many, many OEM boards are made by these guys. Hard to go wrong when the mobos use intel or AMD (ati) chipsets. Also, the entry level boards with the nvidia 6100 series IGPs are so old now, that they are tried and true great entry level IGP boards for office boxes using AMD processors).
3. Gigabyte, Asrock, Biostar, EVGA (just too much enthusiast features at the sake of mild instability if not set up properly).
4. Jetway, Zotac- small time players with no support post purchase.
Now, if you're looking for your own board for a home build where overclocking and voltage options as well as ram timings are important, then the field changes dramatically:
1. Intel (for the gamer oriented boards $100+. Their cheaper line is not very enthusiast friendly) and ASUS-usually the best represented and offers robust features on all but their cheapest boards), and Evga (never used them but have good reviews and seem to build high quality high end boards.) Gigabyte (strongly built boards that should last quite a while and often have all the options you could want. Sometimes offering even more than what ASUS has to offer).
2. Asrock (think of it as the Buick to ASUS's Cadillac. Plenty of the same features for a lot less money, made by generally the same company, and my personal favorite for bang-to-buck ratio. Plenty of great boards from $70 to $100)
3. BIOSTAR/MSI - usually pretty competitive and offer a small amount of overclocking/voltage options at a great price. Their best offerings are in the $40 to $70 dollar range. Not as good for a $100+ board. I've owned several cheapies from these two manufacturers and not had any issues.
4. Foxconn/ECS/Cheap Intel -avoid like the plague. The mobos are generally inflexible to overclocking or other enthusiast hooliganism.
5. Jetway/Zotac- dark horses in the group. Expect no customer service, infrequent or no bios updates, and poorly organized websites. Once you buy it it's your problem, so read the fine print. Only reason to buy is if insanely good bargain price. That being said, I'm typing this on my daily rig running a Jetway AM2 mobo, that's been reliably serving 24/7 duty for the last 3 years now (but I bought it as open box for $30 shipped, IIRC).
I usually buy from the level 2 in each hiarchy, as it gives the best in quality/performance for the money spent.