I understand your point about buying a cheap scope for now or buying a better one for the long term, and I'm not recommending against the Rigol DS1102E. I was just confused by your interest in the Rigol DS2000, while rejecting the Agilent scopes. The cheapest Agilent DSOX2000 series scope is a little over $1000, and I believe the Rigol DS2000 series is expected to be somewhere around $1000, so neither would be a cheap scope.
If you consider the Rigol DS1102E, then I would recommend a second look at the Hantek and Owon scopes. Especially the Hantek scope appears to be a fairly decent scope with better specs in some regard (eg. screen size, update rate). The Owon scopes are a mixed bag in my opinion. Good hardware, especially memory depth, and in many aspects comparable or better than the Hantek (except update rate). Software is clearly inferior, however, and Owon doesn't appear to be working very hard on fixing it. The Rigol DS1102E is definitely the safest, a proven performer compared to Owon and Hantek.
The major banner spec for the DSOX2000 series is the extremely fast update rate, 50 k/second. Something like an order of magnitude more than the Tek DPO2000, and much more than the Rigol DS1102E. Record length is a bit on the small side with 100 kpoints, not as bad as the old 2.5k Tek scopes (eg. TDS2000), but less than the 1 Mpoints of the DPO2000. Cheaper scopes like the Rigol DS1102E will also do 1 Mpoints if you ignore the fastest sweep speeds. The Owon has even more memory. Another cool feature of the Agilent scopes are the ability to upgrade bandwidth or other options. This allows you to buy a 70 MHz scope now and upgrade it to a 200 MHz MSO later (you probably will have to send it to Agilent to have the bandwidth upgraded).
If you're looking for a function generator, you might also consider the Wavegen option for the Agilent scopes. I believe they have only unlocked the arbitrary waveform ability in the 3000 series so far, not in the 2000 series. I don't think the price ($500?) is very attractive compared to a separate function generator, especially without the arb feature. It does make for a nice compact package.
My impression is that Agilent's long term support is better than Tektronix these days, although I wouldn't count on either supporting the instrument for ten years.
The Agilent DSOX 2000/3000 series have been introduced fairly recently. The Tektronix DPO2000/3000/4000 series has been out for a while (DPO2000 was introduced in 2008) and is due for an update to compete with Agilent, but when this is going to happen is anyone's guess. I haven't heard anything concrete, and Tek has an history of underwhelming updates. eg.:
1998: TDS200: 1GS/s, 2.5kpoints, QVGA monochrome display
2002: TDS2000: 0.5-2GS/s, 2.5kpoints, QVGA color display
2006: TDS2000B: 0.5-2GS/s, 2.5kpoints, QVGA color display, adds USB
2010: TDS2000C: 0.5-2GS/s, 2.5kpoints, QVGA color display, adds some automated measurements and other software features
The cheapest Agilent function gen is the 33210A, but arbitrary waveforms are an option that costs another $400. The next higher model is the 33220A, which includes arbitrary waveforms as standard. These are great performers, but quite expensive.