Mt Baker is an enigma. When it's good, you can't beat it. When it's bad, don't go. If someone is planning on a trip to Mt. Baker (like, flying in), don't plan on it being either good or bad. It's all about the weather (obviously), and in some cases, it's like rolling the dice.
Because Mt. Baker is so close to the Pacific ocean, it can be tricky to figure out when to go. The average temp in the north Pacific can be 'warm' and this affects the jet stream (if you don't know what a jet stream is, stop reading and go somewhere else). When there is a bulge in the jet stream near the Gulf of Alaska, and if that stream is sitting off to the west of the NW coast as it comes down, it means the systems hitting the NW will be cold and full of moisture. Why Mt Baker gets so much snow is this: as the systems come in, they are rotating counter-clockwise. Even though the system may be coming from the north, the moisture will be moving SW to NE because of rotation. When this moisture arm hits the Kulshan ridge, where the MB Ski resort is, it has to dump moisture to lift. These moisture arms are funnelled between Mt. Baker and Mt. Shuksan. Kulshan ridge sits perpendicular to these moisture arms, and hence, the big snows that Baker gets. So if you go to Baker, you really have to watch the conditions.
Generally, getting to Baker even from Seattle is a long drive and if you go and conditions suck, that's no good. On the weekends: Mt. Baker is kinda crowded, like any west coast ski resort on any weekend. Additionally, there is no lodging on the mountain and you may not have cell-phone reception. The lodges are nice and the food is decent but not great.
The runs are fun but pretty short. One thing about the runs: if it is a double black diamond, they mean it. Only go if you are an expert. Quite a few runs on Baker are short but intense. To my knowledge, there are few runs at Whistler that are as challenging. Baker is not a great place to learn. If you are learning how to ski or snowboard, go to Snoqualmie Summit near Seattle. The terrain here is much flatter.
If you ever do want to go to Baker, check the weather in Bellingham first. If it's under 45 degrees with rain, there is a good chance the conditions will be right. Mt Baker snow quality is entirely dependant on how cold it gets. Near 32 degrees, not so good, but if it's 25 or under, the composition of the snow will change and it will be a bit drier.