history: I'm about to leave the job I've had for 3 years and go to a new company.  Next week I'm leaving the company I've worked for for 3 years and taking a totally new position at a new company. I'm nervous!  Thats awesome_comma_ never settle for less. Always strive for more!
current: Yes this is definitely an upgrade! I'm just going to be the "new" person and I really do like my current co-workers. 
next: Well hopefully you can still maintain communication with them. It's normal to be nervous though, just go in confident