inconsistent behavior between DataFrame and Series when underlying objects are datetime
I just upgraded from 0.10 to to 0.10.1 to fix a previous issue I had, and i think I'm getting regressions or inconsistent behavior as it relates to issue #2627

the test below is a comparison on 0.10.0 and 0.10.1 under windows 32 bit python 2.7.2

``` python
import numpy
print numpy.__version__
import pandas
from pandas import DataFrame, Series
print pandas.__version__
import datetime

dt1d = [datetime.datetime(2013,1,1) + datetime.timedelta(days= i) for i in range(5)]
dtSeries = pandas.Series(dt1d)
print dtSeries.dtype
print dtSeries.apply(lambda x: x.date())
#this works
print [x.date() for x in dtSeries.values]

dt2d = [[datetime.datetime(2013,1,1) + datetime.timedelta(days= i)] for i in range(5)]
dtDf = DataFrame(dt2d)
print dtDf.dtypes
print dtDf.icol(0).apply(lambda x: x.date())
#the following do not work on 0.10.1 but work on 0.10.0
print [x.date() for x in dtDf.values[:,0]]
print [x.date() for x in dtDf.icol(0).values]
```
## The output for 0.10.0 in ipython:

1.6.2
0.10.0
object
0    2013-01-01
1    2013-01-02
2    2013-01-03
3    2013-01-04
4    2013-01-05
[datetime.date(2013, 1, 1), datetime.date(2013, 1, 2), datetime.date(2013, 1, 3)
, datetime.date(2013, 1, 4), datetime.date(2013, 1, 5)]
0    object
0    2013-01-01
1    2013-01-02
2    2013-01-03
3    2013-01-04
4    2013-01-05
Name: 0
[datetime.date(2013, 1, 1), datetime.date(2013, 1, 2), datetime.date(2013, 1, 3)
, datetime.date(2013, 1, 4), datetime.date(2013, 1, 5)]
[datetime.date(2013, 1, 1), datetime.date(2013, 1, 2), datetime.date(2013, 1, 3)
, datetime.date(2013, 1, 4), datetime.date(2013, 1, 5)]
## The output in 0.10.1:

1.6.2
0.10.1
object
0    2013-01-01
1    2013-01-02
2    2013-01-03
3    2013-01-04
4    2013-01-05
[datetime.date(2013, 1, 1), datetime.date(2013, 1, 2), datetime.date(2013, 1, 3)
, datetime.date(2013, 1, 4), datetime.date(2013, 1, 5)]
0    datetime64[ns]
0    2013-01-01
1    2013-01-02
2    2013-01-03
3    2013-01-04
4    2013-01-05
## Name: 0

AttributeError                            Traceback (most recent call last)
<ipython-input-86-f277941f299d> in <module>()
     18 print dtDf.icol(0).apply(lambda x: x.date())
     19 #the following do not work on 0.10.1 but work on 0.10.0
---> 20 print [x.date() for x in dtDf.values[:,0]]
     21 print [x.date() for x in dtDf.icol(0).values]

AttributeError: 'numpy.datetime64' object has no attribute 'date'
