There are loads of great reasons to be a generalists, both from the perspective of the individual and the company, but there are risks too.
Many people have minds that aren't best suited to specialist, deep, knowledge, but are capable of understanding (and connecting) a broad range of subjects. This isn't to say they're not smart enough to understand detail, more that they're just not interested in that level of information - they'd rather understand lots of things a bit than one thing completely. It often (but not always) combines with a pragmatic approach - being more concerned with what works than what's technically best.
So if that sounds like you, then being a generalist is fine. What you should be concerned with is if you're in a generalist role and frustrated by it, in which case you should look to specialise more.
In terms of the company, from a managers perspective (for I am one), I love having a generalist or two on the team because they're the guys you can drop into any situation and know they'll cope. This might be because the specialist in the area is otherwise occupied (or because your company is too small to have someone full-time in that role), it may be because you simply don't know what skills are going to be needed (generalist are often great at assessing tricky support calls where you have no idea where the root problem is), or because it's the early stages of a project and you have no idea what the eventual solution might look like so want someone who is capable of understanding all the options without automatically trying to steer it towards their own preference.
From a career perspective, generalists the options for generalists are mixed. In some places generalists are the people who get ahead because managers do like them - they're the guys who get things done and aren't precious about it. In other places they suffer because they're never the best at any one thing so they're often seen as steady but unspectacular.
Certainly once you get to a certain level of experience things can be less than ideal. Generalists for obvious reasons often move into management (if is after all just one more thing to be interested in - that's what happened to me), but if they don't it can become harder to progress because you don't necessarily have the huge experience of one thing it takes to stand out. Because of this I'd say if you do intend to stay technical through your career, try and keep some level of focus around what you do (50% of your time or more) as otherwise you will find yourself in a bit of a limbo later on.