One of the works we do as recruiters is to separate the grains from the chaffs, the men from the boys, the ladies from the girls the haves and the have-nots, the diamonds from the coals. In the years that I've been involved in this work I have observed some patterns that separate great candidates from the mediocre ones. Is it their pleasing personality, their ability to articulate, their dilligence or is it their high IQ? I say not. This is of course not to say that these qualities do not come in handy. They do, but they are not the differentiator. You can have all these but if you don't love what you are doing your success becomes limited.
To say that you love your job is much more than paying lip service to it. A spouse for example believes it when he/she is being loved not because of what is heard but because of what is seen and experienced.
You can tell if a person loves his work because s/he invests in getting better at it. I'm not talking about just pursuing continuous education here. I've seen too many people who completed advanced education but have nothing to show for it in terms of quality of work. People who choose to do the things they love put every bit of what they learn to action. Well, maybe not every bit but I'm sure you know what I mean.
These people are updated, up-to-date and continually updating themselves to improve their craft. They take interest in how to do things better and search for a way to do them. If they can't find, they invent, they create.
You know you love your job when you take pride in it. This reminds me of the "bug exterminator" character in that movie Ant Bully. That guy demonstrated an almost obsessive take on his job. Something that is not strange for somebody who really have the love and the passion for what he is doing. I think the best indicator of love for one's work is when one misses it in the same way tha person misses another important person. In short, people who curse Mondays because it means returning to work are people who most likely hate their job.
Every employer wants to hire people who love their job, because these people are great at what they do and are continually getting better. According to Gallup Poll in the US, only about 20% of the working population love their job, the others either like, indifferent or hate their work. Which side of statistic are you in? Again, it's easy to say you love your work, but the important question is how do you show it?