I just tend to see getting new jobs within six months as a warning when I review resumes. I can agree there are different approaches and this area can be especially changeable. My experience with the IT field is if you find a company that gives you respect and the clients don't tick you off too much, it's better to stay. An extra 20k isn't worth the intangibles sometimes.
I've never been a job changer, but I've never been a driven career guy either. I'm sure I could have maxxed out my career more if I'd have aggressively sought out new opportunities a few times.
My career post college graduation:
1 10 years with a bank holding company
2 10 more years with an IT company that had outsourced the data center I worked for in the bank, so really a 20 year tenure.
3 3 years with Quest Diagnostics
4 5 years with a small pharma company that ultimately sold out
5 6 years with my current drug company
That's it. 5 companies in 34 years. 9 more years to go.