[Z-man]

Some questions to the OP that may help him do some self-analysis:

1. What are your main reasons for seeking employement elsewhere? Will more $$ from your current employer alter those reasons? If not, then accepting the counter offer will not change the reasons you sought employement elsewhere. Does the counter include more than just a salary increase? If so, will they resolve the reasons you have for seeking employment elsewhere? (Side note: I have never left a company based on getting more $$ elsewhere -- I do not believe that is the best way to advance one's career)

2. Are you being challenged in your current job?

3. Which company is more stable, your old company, or this new one?

4. Which company offers more opportunities for you to grow and move up?

5. Which company has better benefits? (Medical, retirement, 401(k), vacation, bonus structure, stock options, flexible working schedule...etc.)

6. How long have you been with your current company? How familiar are you with the company's landscape and how things work? Do you like the way things work there?

7. Which place is more suitable for your personality?

8. If you stayed with your current company, are you still an "at will" employee, or can you work up a contract that states they will keep you around for x amount of time? (You may want to have that as part of the counteroffer, to ensure they aren't holding you there until they find someone to replace you)

9. Does the counter offer include a promotion, or just a salary increase? If so, were you soon due a promotion anyway, or did your resignation prompt this?

10. How happy are you at your current job? Does it offer you a satisfying work experience?

Here is what I also suggest:
Divide a piece of paper into 4 quadrants, and label them as such:
Quadrant 1: " Positives for staying with old company"
Quadrant 2: " Negatives for staying with old company"
Quadrant 3: " Positives for going to new company"
Quadrant 4: " Negatives for going to new company"
Now, use 'free thinking' to list all of the aspects of your decision in the appropriate quadrants. Then prioritize them. (Ex: "my commute would be longer if I go to the new company" may be a negative for going to new company, but it is not as high a priority as
"My benefts are significantly less with the new company")

Whatever you do, don't burn any bridges with either company. Even though you have verbally agreed to the new job, they do understand if your present company offered you a counter-offer.

Hope this helps,
-Z-man.